Tags: browser

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Timelines of the web

Recreating the original WorldWideWeb browser was an exercise in digital archeology. With a working NeXT machine in the room, Kimberly was able to examine the source code for the first every browser and discover a treasure trove within. Like this gem in HTUtils.h:

#define TCP_PORT 80 /* Allocated to http by Jon Postel/ISI 24-Jan-92 */

Sure enough, by June of 1992 port 80 was documented as being officially assigned to the World Wide Web (Gopher got port 70). Jean-François Groff—who worked on the World Wide Web project with Tim Berners-Lee—told us that this was a moment they were very pleased about. It felt like this project of theirs was going places.

Jean-François also told us that the WorldWideWeb browser/editor was kind of like an advanced prototype. The idea was to get something up and running as quickly as possible. Well, the NeXT operating system had a very robust Text Object, so the path of least resistance for Tim Berners-Lee was to take the existing word-processing software and build a hypertext component on top of it. Likewise, instead of creating a brand new format, he used the existing SGML format and added one new piece: linking with A tags.

So the WorldWideWeb application was kind of like a word processor and document viewer mashed up with hypertext. Ted Nelson complains to this day that the original sin of the web was that it borrowed this page-based metaphor. But Nelson’s Project Xanadu, originally proposed in 1974 wouldn’t become a working reality until 2014—a gap of forty years. Whereas Tim Berners-Lee proposed his system in March 1989 and had working code within a year. There’s something to be said for being pragmatic and working with what you’ve got.

The web was also a mashup of ideas. Hypertext existed long before the web—Ted Nelson coined the term in 1963. There were conferences and academic discussions devoted to hypertext and hypermedia. But almost all the existing hypertext systems—including Tim Berners-Lee’s own ENQUIRE system from the early 80s—were confined to a local machine. Meanwhile networked computers were changing everything. First there was the ARPANET, then the internet. Tim Berners-Lee’s ambitious plan was to mash up hypertext with networks.

Going into our recreation of WorldWideWeb at CERN, I knew I wanted to convey this historical context somehow.

The World Wide Web officially celebrates its 30th birthday in March of this year. It’s kind of an arbitrary date: it’s the anniversary of the publication of Information Management: A Proposal. Perhaps a more accurate date would be the day the first website—and first web server—went online. But still. Let’s roll with this date of March 12, 1989. I thought it would be interesting not only to look at what’s happened between 1989 and 2019, but also to look at what happened between 1959 and 1989.

So now I’ve got two time cones that converge in the middle: 1959 – 1989 and 1989 – 2019. For the first time period, I made categories of influences: formats, hypertext, networks, and computing. For the second time period, I catalogued notable results: browsers, servers, and the evolution of HTML.

I did a little bit of sketching and quickly realised that these converging timelines could be represented somewhat like particle collisions. Once I had that idea in my head, I knew how I would be spending my time during the hack week.

Rather than jumping straight into the collider visualisation, I took some time to make a solid foundation to build on. I wanted to be sure that the timeline itself would be understable even if it were, say, viewed in the first ever web browser.

Progressive enhancement. Marking up (and styling) an interactive timeline that looks good in a modern browser and still works in the first ever web browser.

I marked up each timeline as an ordered list of h-events:

<li class="h-event y1968">
  <a href="https://en.wikipedia.org/wiki/NLS_%28computer_system%29" class="u-url">
    <time class="dt-start" datetime="1968-12-09">1968</time>
    <abbr class="p-name" title="oN-Line System">NLS</abbr>
  </a>
</li>

With the markup in place, I could concentrate on making it look halfway decent. For small screens, the layout is very basic—just a series of lists. When the screen gets wide enough, I lay those lists out horzontally one on top of the other. In this view, you can more easily see when events coincide. For example, ENQUIRE, Usenet, and Smalltalk all happen in 1980. But the real beauty comes when the screen is wide enough to display everthing at once. You can see how an explosion of activity in the early 90s. In 1994 alone, we get the release of Netscape Navigator, the creation of HTTPS, and the launch of Amazon.com.

The whole thing is powered by CSS transforms and positioning. Each year on a timeline has its own class that gets moved to the correct chronological point using calc(). I wanted to use translateX() but I couldn’t get the maths to work for that, so I had use plain ol’ left and right:

.y1968 {
  left: calc((1968 - 1959) * (100%/30) - 5em);
}

For events before 1989, it’s the distance of the event from 1959. For events after 1989, it’s the distance of the event from 2019:

.y2014 {
  right: calc((2019 - 2014) * (100%/30) - 5em);
}

(Each h-event has a width of 5em so that’s where the extra bit at the end comes from.)

I had to do some tweaking for legibility: bunches of events happening around the same time period needed to be separated out so that they didn’t overlap too much.

As a finishing touch, I added a few little transitions when the page loaded so that the timeline fans out from its centre point.

Et voilà!

Progressive enhancement. Marking up (and styling) an interactive timeline that looks good in a modern browser and still works in the first ever web browser.

I fiddled with the content a bit after peppering Robert Cailliau with questions over lunch. And I got some very valuable feedback from Jean-François. Some examples he provided:

1971: Unix man pages, one of the first instances of writing documents with a markup language that is interpreted live by a parser before being presented to the user.

1980: Usenet News, because it was THE everyday discussion medium by the time we created the web technology, and the Web first embraced news as a built-in information resource, then various platforms built on the web rendered it obsolete.

1982: Literary Machines, Ted Nelson’s book which was on our desk at all times

I really, really enjoyed building this “collider” timeline. It was a chance for me to smash together my excitement for web history with my enjoyment of using the raw materials of the web; HTML and CSS in this case.

The timeline pales in comparison to the achievement of the rest of the team in recreating the WorldWideWeb application but I was just glad to be able to contribute a little something to the project.

Hello WorldWideWeb.

WorldWideWeb

Nine people came together at CERN for five days and made something amazing. I still can’t quite believe it.

Coming into this, I thought it was hugely ambitious to try to not only recreate the experience of using the first ever web browser (called WorldWideWeb, later Nexus), but to also try to document the historical context of the time. Now that it’s all done, I’m somewhat astounded that we managed to achieve both.

Want to see the final result? Here you go:

worldwideweb.cern.ch

That’s the website we built. The call to action is hard to miss:

Launch WorldWideWeb

Behold! A simulation of using the first ever web browser, recreated inside your web browser.

Now you could try clicking around on the links on the opening doucment—remembering that you need to double-click on links to activate them—but you’ll quickly find that most of them don’t work. They’re long gone. So it’s probably going to be more fun to open a new page to use as your starting point. Here’s how you do that:

  1. Select Document from the menu options on the left.
  2. A new menu will pop open. Select Open from full document reference.
  3. Type a URL, like, say https://adactio.com
  4. Press that lovely chunky Open button.

You are now surfing the web through a decades-old interface. Double click on a link to open it. You’ll notice that it opens in a new window. You’ll also notice that there’s no way of seeing the current URL. Back then, the idea was that you would navigate primarily by clicking on links, creating your own “associative trails”, as first envisioned by Vannevar Bush.

But the WorldWideWeb application wasn’t just a browser. It was a Hypermedia Browser/Editor.

  1. From that Document menu you opened, select New file…
  2. Type the name of your file; something like test.html
  3. Start editing the heading and the text.
  4. In the main WorldWideWeb menu, select Links.
  5. Now focus the window with the document you opened earlier (adactio.com).
  6. With that window’s title bar in focus, choose Mark all from the Links menu.
  7. Go back to your test.html document, and highlight a piece of text.
  8. With that text highlighted, click on Link to marked from the Links menu.

If you want, you can even save the hypertext document you created. Under the Document menu there’s an option to Save a copy offline (this is the one place where the wording of the menu item isn’t exactly what was in the original WorldWideWeb application). Save the file so you can open it up in a text editor and see what the markup would’ve looked it.

I don’t know about you, but I find this utterly immersive and fascinating. Imagine what it must’ve been like to browse, create, and edit like this. Hypertext existed before the web, but it was confined to your local hard drive. Here, for the first time, you could create links across networks!

After five days time-travelling back thirty years, I have a new-found appreciation for what Tim Berners-Lee created. But equally, I’m in awe of what my friends created thirty years later.

Remy did all the JavaScript for the recreated browser …in just five days!

Kimberly was absolutely amazing, diving deep into the original source code of the application on the NeXT machine we borrowed. She uncovered some real gems.

Of course Mark wanted to make sure the font was as accurate as possible. He and Brian went down quite a rabbit hole, and with remote help from David Jonathan Ross, they ended up recreating entire families of fonts.

John exhaustively documented UI patterns that Angela turned into marvelous HTML and CSS.

Through it all, Craig and Martin put together the accomanying website. Personally, I think the website is freaking awesome—it’s packed with fascinating information! Check out the family tree of browsers that Craig made.

What a team!

Back at CERN

We got the band back together.

In September of 2013, I had the great pleasure and privilege of going to CERN with a bunch of very smart people. I’m not sure how I managed to slip by. We were there to recreate the experience of using the line-mode browser. As I wrote at the time:

Just to be clear, the line-mode browser wasn’t the world’s first web browser. That honour goes to Tim Berners-Lee’s WorldWideWeb programme. But whereas WorldWideWeb only ran on NeXT machines, the line-mode browser worked cross-platform and was, therefore, instrumental in demonstrating the power of the web as a universally-accessible medium.

In the run-up to the 30th anniversary of the original (vague but exciting) proposal for what would become the World Wide Web, we’ve been invited back to try to recreate the experience of using that first web browser, the one that one ever ran on NeXT machines.

I missed the first day due to travel madness—flying back from Interaction 19 in Seattle during snowmageddon to Heathrow and then to Geneva—but by the time I arrived, my hackmates had already made a great start in identifying the objectives:

  1. Give people an understanding of the user experience of the WorldWideWeb browser.
  2. Demonstrate that a read/write philosophy was there from the beginning.
  3. Give context—what was going on at the time?

That second point is crucial. WorldWideWeb wasn’t just a web browser; it was a browser/editor. That’s by far the biggest change in terms of the original vision of the web and what we ended up getting from Mosaic onwards.

Remy is working hard on the first point. He documented the first day and now on the second day, he’s made enormous progress already.

I’m focusing on point number three. I want to show the historical context for the World Wide Web. Here’s my plan…

Seeing as we’re coming up on the thirtieth anniversary, I thought it would be interesting to take the year of the proposal (1989) and look back in a time cone of thirty years previous to that at the influences on Tim Berners-Lee. I also want to look at what has happened with the web in the thirty years since the proposal. So the date of the proposal will be a centre point, with the timespan of 1959-1989 converging on it from the past, and the timespan of 1989-2019 diverging from it into the future. I hope it could make for a nice visualisation. Maybe I could try to get it look like data from a particle collision.

We’re here till the weekend and everyone else has already made tremendous progress. Kimberly has been hacking the Gibson …well, that’s what it looked like when she was deep in the code of the NeXT machine we’ve borrowed from Musée Bolo (merci beaucoup!).

We took a little time out for a tour of the data centre. Oh, and at lunch time, we sat with Robert Cailliau and grilled him with questions about the birth of the web. Quite a day!

Now it’s time for me to hit the hay and prepare for another day of hacking in this extraordinary place.

Ch-ch-ch-changes

It’s browser updatin’ time! Firefox 65 just dropped. So did Chrome 72. Safari 12.1 is shipping with iOS 12.2.

It’s interesting to compare the release notes for each browser and see the different priorities reflected in them (this is another reason why browser diversity is A Good Thing).

A lot of the Firefox changes are updates to dev tools; they just keep getting better and better. In fact, I’m not sure “dev tools” is the right word for them. With their focus on layout, typography, and accessibility, “design tools” might be a better term.

Oh, and Firefox is shipping support for some CSS properties that really help with print style sheets, so I’m disproportionately pleased about that.

In Safari’s changes, I’m pleased to see that the datalist element is finally getting implemented. I’ve been a fan of that element for many years now. (Am I a dork for having favourite HTML elements? Or am I a dork for even having to ask that question?)

And, of course, it wouldn’t be a Safari release without a new made up meta tag. From the people who brought you such hits as viewport and apple-mobile-web-app-capable, comes …supported-color-schemes (Apple likes to make up meta tags almost as much as Google likes to make up rel values).

There’ll be a whole bunch of improvements in how progressive web apps will behave once they’ve been added to the home screen. We’ll finally get some state persistence if you navigate away from the window!

Updated the behavior of websites saved to the home screen on iOS to pause in the background instead of relaunching each time.

Maximiliano Firtman has a detailed list of the good, the bad, and the “not sure yet if good” for progressive web apps on iOS 12.2 beta. Thomas Steiner has also written up the progress of progressive web apps in iOS 12.2 beta. Both are published on Ev’s blog.

At first glance, the release notes for Chrome 72 are somewhat paltry. The big news doesn’t even seem to be listed there. Maximiliano Firtman again:

Chrome 72 for Android shipped the long-awaited Trusted Web Activity feature, which means we can now distribute PWAs in the Google Play Store!

Very interesting indeed! I’m not sure if I’m ready to face the Kafkaesque process of trying to add something to the Google Play Store just yet, but it’s great to know that I can. Combined with the improvements coming in iOS 12.2, these are exciting times for progressive web apps!

Browsers

Microsoft’s Edge browser is going to switch its rendering engine over to Chromium.

I am deflated and disappointed.

There’s just no sugar-coating this. I’m sure the decision makes sound business sense for Microsoft, but it’s not good for the health of the web.

Very soon, the vast majority of browsers will have an engine that’s either Blink or its cousin, WebKit. That may seem like good news for developers when it comes to testing, but trust me, it’s a sucky situation of innovation and agreement. Instead of a diverse browser ecosystem, we’re going to end up with incest and inbreeding.

There’s one shining exception though. Firefox. That browser was originally created to combat the seemingly unstoppable monopolistic power of Internet Explorer. Now that Microsoft are no longer in the rendering engine game, Firefox is once again the only thing standing in the way of a complete monopoly.

I’ve been using Firefox as my main browser for a while now, and I can heartily recommend it. You should try it (and maybe talk to your relatives about it at Christmas). At this point, which browser you use no longer feels like it’s just about personal choice—it feels part of something bigger; it’s about the shape of the web we want.

Jeffrey wrote that browser diversity starts with us:

The health of Firefox is critical now that Chromium will be the web’s de facto rendering engine.

Even if you love Chrome, adore Gmail, and live in Google Docs or Analytics, no single company, let alone a user-tracking advertising giant, should control the internet.

Andy Bell also writes about browser diversity:

I’ll say it bluntly: we must support Firefox. We can’t, as a community allow this browser engine monopoly. We must use Firefox as our main dev browsers; we must encourage our friends and families to use it, too.

Yes, it’s not perfect, nor are Mozilla, but we can help them to develop and grow by using Firefox and reporting issues that we find. If we just use and build for Chromium, which is looking likely (cough Internet Explorer monopoly cough), then Firefox will fall away and we will then have just one major engine left. I don’t ever want to see that.

Uncle Dave says:

If the idea of a Google-driven Web is of concern to you, then I’d encourage you to use Firefox. And don’t be a passive consumer; blog, tweet, and speak about its killer features. I’ll start: Firefox’s CSS Grid, Flexbox, and Variable Font tools are the best in the business.

Mozilla themselves came out all guns blazing when they said Goodbye, EdgeHTML:

Microsoft is officially giving up on an independent shared platform for the internet. By adopting Chromium, Microsoft hands over control of even more of online life to Google.

Tim describes the situation as risking a homogeneous web:

I don’t think Microsoft using Chromium is the end of the world, but it is another step down a slippery slope. It’s one more way of bolstering the influence Google currently has on the web.

We need Google to keep pushing the web forward. But it’s critical that we have other voices, with different viewpoints, to maintain some sense of balance. Monocultures don’t benefit anyone.

Andre Alves Garzia writes that while we Blink, we lose the web:

Losing engines is like losing languages. People may wish that everyone spoke the same language, they may claim it leads to easier understanding, but what people fail to consider is that this leads to losing all the culture and way of thought that that language produced. If you are a Web developer smiling and happy that Microsoft might be adopting Chrome, and this will make your work easier because it will be one less browser to test, don’t be! You’re trading convenience for diversity.

I like that analogy with language death. If you prefer biological analogies, it’s worth revisiting this fantastic post by Rachel back in August—before any of us knew about Microsoft’s decision—all about the ecological impact of browser diversity:

Let me be clear: an Internet that runs only on Chrome’s engine, Blink, and its offspring, is not the paradise we like to imagine it to be.

That post is a great history lesson, documenting how things can change, and how decisions can have far-reaching unintended consequences.

So these are the three browser engines we have: WebKit/Blink, Gecko, and EdgeHTML. We are unlikely to get any brand new bloodlines in the foreseeable future. This is it.

If we lose one of those browser engines, we lose its lineage, every permutation of that engine that would follow, and the unique takes on the Web it could allow for.

And it’s not likely to be replaced.

Push without notifications

On the first day of Indie Web Camp Berlin, I led a session on going offline with service workers. This covered all the usual use-cases: pre-caching; custom offline pages; saving pages for offline reading.

But on the second day, Sebastiaan spent a fair bit of time investigating a more complex use of service workers with the Push API.

The Push API is what makes push notifications possible on the web. There are a lot of moving parts—browser, server, service worker—and, frankly, it’s way over my head. But I’m familiar with the general gist of how it works. Here’s a typical flow:

  1. A website prompts the user for permission to send push notifications.
  2. The user grants permission.
  3. A whole lot of complicated stuff happens behinds the scenes.
  4. Next time the website publishes something relevant, it fires a push message containing the details of the new URL.
  5. The user’s service worker receives the push message (even if the site isn’t open).
  6. The service worker creates a notification linking to the URL, interrupting the user, and generally adding to the weight of information overload.

Here’s what Sebastiaan wanted to investigate: what if that last step weren’t so intrusive? Here’s the alternate flow he wanted to test:

  1. A website prompts the user for permission to send push notifications.
  2. The user grants permission.
  3. A whole lot of complicated stuff happens behinds the scenes.
  4. Next time the website publishes something relevant, it fires a push message containing the details of the new URL.
  5. The user’s service worker receives the push message (even if the site isn’t open).
  6. The service worker fetches the contents of the URL provided in the push message and caches the page. Silently.

It worked.

I think this could be a real game-changer. I don’t know about you, but I’m very, very wary of granting websites the ability to send me push notifications. In fact, I don’t think I’ve ever given a website permission to interrupt me with push notifications.

You’ve seen the annoying permission dialogues, right?

In Firefox, it looks like this:

Will you allow name-of-website to send notifications?

[Not Now] [Allow Notifications]

In Chrome, it’s:

name-of-website wants to

Show notifications

[Block] [Allow]

But in actual fact, these dialogues are asking for permission to do two things:

  1. Receive messages pushed from the server.
  2. Display notifications based on those messages.

There’s no way to ask for permission just to do the first part. That’s a shame. While I’m very unwilling to grant permission to be interrupted by intrusive notifications, I’d be more than willing to grant permission to allow a website to silently cache timely content in the background. It would be a more calm technology.

Think of the use cases:

  • I grant push permission to a magazine. When the magazine publishes a new article, it’s cached on my device.
  • I grant push permission to a podcast. Whenever a new episode is published, it’s cached on my device.
  • I grant push permission to a blog. When there’s a new blog post, it’s cached on my device.

Then when I’m on a plane, or in the subway, or in any other situation without a network connection, I could still visit these websites and get content that’s fresh to me. It’s kind of like background sync in reverse.

There’s plenty of opportunity for abuse—the cache could get filled with content. But websites can already do that, and they don’t need to be granted any permissions to do so; just by visiting a website, it can add multiple files to a cache.

So it seems that the reason for the permissions dialogue is all about displaying notifications …not so much about receiving push messages from the server.

I wish there were a way to implement this background-caching pattern without requiring the user to grant permission to a dialogue that contains the word “notification.”

I wonder if the act of adding a site to the home screen could implicitly grant permission to allow use of the Push API without notifications?

In the meantime, the proposal for periodic synchronisation (using background sync) could achieve similar results, but in a less elegant way; periodically polling for new content instead of receiving a push message when new content is published. Also, it requires permission. But at least in this case, the permission dialogue should be more specific, and wouldn’t include the word “notification” anywhere.

Service workers and videos in Safari

Alright, so I’ve already talked about some gotchas when debugging service worker issues. But what if you don’t even realise the problem has anything to do with your service worker?

This is not a hypothetical situation. I encountered this very thing myself. Gather ‘round the campfire, children…

One of the latest case studies on the Clearleft site is a nice write-up by Luke of designing a mobile app for Virgin Holidays. The case study includes a lovely video that demonstrates the log-in flow. I implemented that using a video element (with a poster image). Nice and straightforward. Super easy. All good.

But I hadn’t done my due diligence in browser testing (I guess I didn’t even think of it in this case). Hana informed me that the video wasn’t working at all in Safari. The poster image appeared just fine, but when you clicked on it, the video didn’t load.

I ducked, ducked, and went, uncovering what appeared to be the root of the problem. It seems that Safari is fussy about having servers support something called “byte-range requests”.

I had put the video in question on an Amazon S3 server. I came to the conclusion that S3 mustn’t support these kinds of headers correctly, or something.

Now I had a diagnosis. The next step was figuring out a solution. I thought I might have to move the video off of S3 and onto a server that I could configure a bit more.

Luckily, I never got ‘round to even starting that process. That’s good. Because it turns out that my diagnosis was completely wrong.

I came across a recent post by Phil Nash called Service workers: beware Safari’s range request. The title immediately grabbed my attention. Safari: yes! Video: yes! But service workers …wait a minute!

There’s a section in Phil’s post entitled “Diagnosing the problem”, in which he says:

I first thought it could have something to do with the CDN I’m using. There were some false positives regarding streaming video through a CDN that resulted in some extra research that was ultimately fruitless.

That described my situation exactly. Except Phil went further and nailed down the real cause of the problem:

Nginx was serving correct responses to Range requests. So was the CDN. The only other problem? The service worker. And this broke the video in Safari.

Doh! I hadn’t even thought about service workers!

Phil came up with a solution, and he has kindly shared his code.

I decided to go for a dumber solution:

if ( request.url.match(/\.(mp4)$/) ) {
  return;
}

That tells the service worker to just step out of the way when it comes to video requests. Now the video plays just fine in Safari. It’s a bit of a shame, because I’m kind of penalising all browsers for Safari’s bug, but the Clearleft site isn’t using much video at all, and in any case, it might be good not to fill up the cache with large video files.

But what’s more important than any particular solution is correctly identifying the problem. I’m quite sure I never would’ve been able to fix this issue if Phil hadn’t gone to the trouble of sharing his experience. I’m very, very grateful that he did.

That’s the bigger lesson here: if you solve a problem—even if you think it’s hardly worth mentioning—please, please share your solution. It could make all the difference for someone out there.

Service workers and browser extensions

I quite enjoy a good bug hunt. Just yesterday, myself and Cassie were doing some bugfixing together. As always, the first step was to try to reproduce the problem and then isolate it. Which reminds me…

There’ve been a few occasions when I’ve been trying to debug service worker issues. The problem is rarely in reproducing the issue—it’s isolating the cause that can be frustrating. I try changing a bit of code here, and a bit of code there, in an attempt to zero in on the problem, butwith no luck. Before long, I’m tearing my hair out staring at code that appears to have nothing wrong with it.

And that’s when I remember: browser extensions.

I’m currently using Firefox as my browser, and I have extensions installed to stop tracking and surveillance (these technologies are usually referred to as “ad blockers”, but that’s a bit of a misnomer—the issue isn’t with the ads; it’s with the invasive tracking).

If you think about how a service worker does its magic, it’s as if it’s sitting in the browser, waiting to intercept any requests to a particular domain. It’s like the service worker is the first port of call for any requests the browser makes. But then you add a browser extension. The browser extension is also waiting to intercept certain network requests. Now the extension is the first port of call, and the service worker is relegated to be next in line.

This, apparently, can cause issues (presumably depending on how the browser extension has been coded). In some situations, network requests that should work just fine start to fail, executing the catch clauses of fetch statements in your service worker.

So if you’ve been trying to debug a service worker issue, and you can’t seem to figure out what the problem might be, it’s not necessarily an issue with your code, or even an issue with the browser.

From now on when I’m troubleshooting service worker quirks, I’m going to introduce a step zero, before I even start reproducing or isolating the bug. I’m going to ask myself, “Are there any browser extensions installed?”

I realise that sounds as basic as asking “Are you sure the computer is switched on?” but there’s nothing wrong with having a checklist of basic questions to ask before moving on to the more complicated task of debugging.

I’m going to make a checklist. Then I’m going to use it …every time.

Service workers in Samsung Internet browser

I was getting reports of some odd behaviour with the service worker on thesession.org, the Irish music website I run. Someone emailed me to say that they kept getting the offline page, even when their internet connection was perfectly fine and the site was up and running.

They didn’t mind answering my pestering follow-on questions to isolate the problem. They told me that they were using the Samsung Internet browser on Android. After a little searching, I found this message on a Github thread about using waitUntil. It’s from someone who works on the Samsung Internet team:

Sadly, the asynchronos waitUntil() is not implemented yet in our browser. Yes, we will implement it but our release cycle is so far. So, for a long time, we might not resolve the issue.

A-ha! That explains the problem. See, here’s the pattern I was using:

  1. When someone requests a file,
  2. fetch that file from the network,
  3. create a copy of the file and cache it,
  4. return the contents.

Step 1 is the event listener:

// 1. When someone requests a file
addEventListener('fetch', fetchEvent => {
  let request = fetchEvent.request;
  fetchEvent.respondWith(

Steps 2, 3, and 4 are inside that respondWith:

// 2. fetch that file from the network
fetch(request)
.then( responseFromFetch => {
  // 3. create a copy of the file and cache it
  let copy = responseFromFetch.clone();
  caches.open(cacheName)
  .then( cache => {
    cache.put(request, copy);
  })
  // 4. return the contents.
  return responseFromFetch;
})

Step 4 might well complete while step 3 is still running (remember, everything in a service worker script is asynchronous so even though I’ve written out the steps sequentially, you never know what order the steps will finish in). That’s why I’m wrapping that third step inside fetchEvent.waitUntil:

// 2. fetch that file from the network
fetch(request)
.then( responseFromFetch => {
  // 3. create a copy of the file and cache it
  let copy = responseFromFetch.clone();
  fetchEvent.waitUntil(
    caches.open(cacheName)
    .then( cache => {
      cache.put(request, copy);
    })
  );
  // 4. return the contents.
  return responseFromFetch;
})

If a browser (like Samsung Internet) doesn’t understand the bit where I say fetchEvent.waitUntil, then it will throw an error and execute the catch clause. That’s where I have my fifth and final step: “try looking in the cache instead, but if that fails, show the offline page”:

.catch( fetchError => {
  console.log(fetchError);
  return caches.match(request)
  .then( responseFromCache => {
    return responseFromCache || caches.match('/offline');
  });
})

Normally in this kind of situation, I’d use feature detection to check whether a browser understands a particular API method. But it’s a bit tricky to test for support for asynchronous waitUntil. That’s okay. I can use a try/catch statement instead. Here’s what my revised code looks like:

fetch(request)
.then( responseFromFetch => {
  let copy = responseFromFetch.clone();
  try {
    fetchEvent.waitUntil(
      caches.open(cacheName)
      .then( cache => {
        cache.put(request, copy);
      })
    );
  } catch (error) {
    console.log(error);
  }
  return responseFromFetch;
})

Now I’ve managed to localise the error. If a browser doesn’t understand the bit where I say fetchEvent.waitUntil, it will execute the code in the catch clause, and then carry on as usual. (I realise it’s a bit confusing that there are two different kinds of catch clauses going on here: on the outside there’s a .then()/.catch() combination; inside is a try{}/catch{} combination.)

At some point, when support for async waitUntil statements is universal, this precautionary measure won’t be needed, but for now wrapping them inside try doesn’t do any harm.

There are a few places in chapter five of Going Offline—the chapter about service worker strategies—where I show examples using async waitUntil. There’s nothing wrong with the code in those examples, but if you want to play it safe (especially while Samsung Internet doesn’t support async waitUntil), feel free to wrap those examples in try/catch statements. But I’m not going to make those changes part of the errata for the book. In this case, the issue isn’t with the code itself, but with browser support.

Console methods

Whenever I create a fetch event inside a service worker, my code roughly follows the same pattern. There’s a then clause which gets executed if the fetch is successful, and a catch clause in case anything goes wrong:

fetch( request)
.then( fetchResponse => {
    // Yay! It worked.
})
.catch( fetchError => {
    // Boo! It failed.
});

In my book—Going Offline—I’m at pains to point out that those arguments being passed into each clause are yours to name. In this example I’ve called them fetchResponse and fetchError but you can call them anything you want.

I always do something with the fetchResponse inside the then clause—either I want to return the response or put it in a cache.

But I rarely do anything with fetchError. Because of that, I’ve sometimes made the mistake of leaving it out completely:

fetch( request)
.then( fetchResponse => {
    // Yay! It worked.
})
.catch( () => {
    // Boo! It failed.
});

Don’t do that. I think there’s some talk of making the error argument optional, but for now, some browsers will get upset if it’s not there.

So always include that argument, whether you call it fetchError or anything else. And seeing as it’s an error, this might be a legitimate case for outputing it to the browser’s console, even in production code.

And yes, you can output to the console from a service worker. Even though a service worker can’t access anything relating to the document object, you can still make use of window.console, known to its friends as console for short.

My muscle memory when it comes to sending something to the console is to use console.log:

fetch( request)
.then( fetchResponse => {
    return fetchResponse;
})
.catch( fetchError => {
    console.log(fetchError);
});

But in this case, the console.error method is more appropriate:

fetch( request)
.then( fetchResponse => {
    return fetchResponse;
})
.catch( fetchError => {
    console.error(fetchError);
});

Now when there’s a connectivity problem, anyone with a console window open will see the error displayed bold and red.

If that seems a bit strident to you, there’s always console.warn which will still make the output stand out, but without being quite so alarmist:

fetch( request)
.then( fetchResponse => {
    return fetchResponse;
})
.catch( fetchError => {
    console.warn(fetchError);
});

That said, in this case, console.error feels like the right choice. After all, it is technically an error.

Switching

Chris has written about switching code editors. I’m a real stick-in-the-mud when it comes to switching editors. Partly that’s because I’m generally pretty happy with whatever I’m using (right now it’s Atom) but it’s also because I just don’t get that excited about software like this. I probably should care more; I spend plenty of time inside a code editor. And I should really take the time to get to grips with features like keyboard shortcuts—I’m sure I’m working very inefficiently. But, like I said, I find it hard to care enough, and on the whole, I’m content.

I was struck by this observation from Chris:

When moving, I have to take time to make sure it works pretty much like the old one.

That reminded me of a recent switch I made, not with code editors, but with browsers.

I’ve been using Chrome for years. One day it started crashing a lot. So I decided to make the switch to Firefox. Looking back, I’m glad to have had this prompt—I think it’s good to shake things up every now and then, so I don’t get too complacent (says the hypocrite who can’t be bothered to try a new code editor).

Just as Chris noticed with code editors, it was really important that I could move bookmarks (and bookmarklets!) over to my new browser. On the whole, it went pretty smoothly. I had to seek out a few browser extensions but that was pretty much it. And because I use a password manager, logging into all my usual services wasn’t a hassle.

Of all the pieces of software on my computer, the web browser is the one where I definitely spend the most time: reading, linking, publishing. At this point, I’m very used to life with Firefox as my main browser. It’s speedy and stable, and the dev tools are very similar to Chrome’s.

Maybe I’ll switch to Safari at some point. Like I said, I think it’s good to shake things up and get out of my comfort zone.

Now, if I really wanted to get out of my comfort zone, I’d switch operating systems like Dave did with his move to Windows. And I should really try using a different phone OS. Again, this is something that Dave tried with his switch to Android (although that turned out to be unacceptably creepy), and Paul did it ages ago using a Windows phone for a week.

There’s probably a balance to be struck here. I think it’s good to change code editors, browsers, even operating systems and phones every now and then, but I don’t want to feel like I’m constantly in learning mode. There’s something to be said for using tools that are comfortable and familiar, even if they’re outdated.

CSS grid in Internet Explorer 11

When I was in Boston, speaking on a lunchtime panel with Rachel at An Event Apart, we took some questions from the audience about CSS grid. Inevitably, a question about browser support came up—specifically about support in Internet Explorer 11.

(Technically, you can use CSS grid in IE11—in fact it was the first browser to ship a version of grid—but the prefixed syntax is different to the standard and certain features are missing.)

Rachel gave a great balanced response, saying that you need to look at your site’s stats to determine whether it’s worth the investment of your time trying to make a grid work in IE11.

My response was blunter. I said I just don’t consider IE11 as a browser that supports grid.

Now, that might sound harsh, but what I meant was: you’re already dividing your visitors into browsers that support grid, and browsers that don’t …and you’re giving something to those browsers that don’t support grid. So I’m suggesting that IE11 falls into that category and should receive the layout you’re giving to browsers that don’t support grid …because really, IE11 doesn’t support grid: that’s the whole reason why the syntax is namespaced by -ms.

You could jump through hoops to try to get your grid layout working in IE11, as detailed in a three-part series on CSS Tricks, but at that point, the amount of effort you’re putting in negates the time-saving benefits of using CSS grid in the first place.

Frankly, the whole point of prefixed CSS is that is not used after a reasonable amount of time (originally, the idea was that it would not be used in production, but that didn’t last long). As we’ve moved away from prefixes to flags in browsers, I’m seeing the amount of prefixed properties dropping, and that’s very, very good. I’ve stopped using autoprefixer on new projects, and I’ve been able to remove it from some existing ones—please consider doing the same.

And when it comes to IE11, I’ll continue to categorise it as a browser that doesn’t support CSS grid. That doesn’t mean I’m abandoning users of IE11—far from it. It means I’m giving them the layout that’s appropriate for the browser they’re using.

Remember, websites do not need to look exactly the same in every browser.

Registering service workers

In chapter two of Going Offline, I talk about registering your service worker wrapped up in some feature detection:

<script>
if (navigator.serviceworker) {
  navigator.serviceworker.register('/serviceworker.js');
}
</script>

But I also make reference to a declarative way of doing this that isn’t very widely supported:

<link rel="serviceworker" href="/serviceworker.js">

No need for feature detection there. Thanks to the liberal error-handling model of HTML (and CSS), browsers will just ignore what they don’t understand, which isn’t the case with JavaScript.

Alas, it looks like that nice declarative alternative isn’t going to be making its way into browsers anytime soon. It has been removed from the HTML spec. That’s a shame. I have a preference for declarative solutions where possible—they’re certainly easier to teach. But in this case, the JavaScript alternative isn’t too onerous.

So if you’re reading Going Offline, when you get to the bit about someday using the rel value, you can cast a wistful gaze into the distance, or shed a tiny tear for what might have been …and then put it out of your mind and carry on reading.

Expectations

I noticed something interesting recently about how I browse the web.

It used to be that I would notice if a site were responsive. Or, before responsive web design was a thing, I would notice if a site was built with a fluid layout. It was worthy of remark, because it was exceptional—the default was fixed-width layouts.

But now, that has flipped completely around. Now I notice if a site isn’t responsive. It feels …broken. It’s like coming across an embedded map that isn’t a slippy map. My expectations have reversed.

That’s kind of amazing. If you had told me ten years ago that liquid layouts and media queries would become standard practice on the web, I would’ve found it very hard to believe. I spent the first decade of this century ranting in the wilderness about how the web was a flexible medium, but I felt like the laughable guy on the street corner with an apocalyptic sandwich board. Well, who’s laughing now

Anyway, I think it’s worth stepping back every now and then and taking stock of how far we’ve come. Mind you, in terms of web performance, the trend has unfortunately been in the wrong direction—big, bloated websites have become the norm. We need to change that.

Now, maybe it’s because I’ve been somewhat obsessed with service workers lately, but I’ve started to notice my expectations around offline behaviour changing recently too. It’s not that I’m surprised when I can’t revisit an article without an internet connection, but I do feel disappointed—like an opportunity has been missed.

I really notice it when I come across little self-contained browser-based games like

Those games are great! I particularly love Battleship Solitaire—it has a zen-like addictive quality to it. If I load it up in a browser tab, I can then safely go offline because the whole game is delivered in the initial download. But if I try to navigate to the game while I’m offline, I’m out of luck. That’s a shame. This snack-sized casual games feel like the perfect use-case for working offline (or, even if there is an internet connection, they could still be speedily served up from a cache).

I know that my expectations about offline behaviour aren’t shared by most people. The idea of visiting a site even when there’s no internet connection doesn’t feel normal …yet.

But perhaps that expectation will change. It’s happened before.

(And if you want to be ready when those expectations change, I’ve written a Going Offline for you.)

Timing

Apple Inc. is my accidental marketing department.

On April 29th, 2010, Steve Jobs published his infamous Thoughts on Flash. It thrust the thitherto geek phrase “HTML5” into the mainstream press:

HTML5, the new web standard that has been adopted by Apple, Google and many others, lets web developers create advanced graphics, typography, animations and transitions without relying on third party browser plug-ins (like Flash). HTML5 is completely open and controlled by a standards committee, of which Apple is a member.

Five days later, I announced the first title from A Book Apart: HTML5 For Web Designers. The timing was purely coincidental, but it definitely didn’t hurt that book’s circulation.

Fast forward eight years…

On March 29th, 2018, Apple released the latest version of iOS. Unmentioned in the press release, this update added service worker support to Mobile Safari.

Five days later, I announced the 26th title from A Book Apart: Going Offline.

For a while now, quite a few people have cited Apple’s lack of support as a reason why they weren’t investigating service workers. That excuse no longer holds water.

Once again, the timing is purely coincidental. But it can’t hurt.

Understandable excitement

An Event Apart Seattle just wrapped. It was a three-day special edition and it was really rather good. Lots of the speakers (myself included) were unveiling brand new talks, so there was a real frisson of excitement.

It was interesting to see repeating, overlapping themes. From a purely technical perspective, three technologies that were front and centre were:

  • CSS grid,
  • variable fonts, and
  • service workers.

From listening to other attendees, the overwhelming message received was “These technologies are here—they’ve arrived.” Now, depending on your mindset, that understanding can be expressed as “Oh shit! These technologies are here!” or “Yay! Finally! These technologies are here!”

My reaction is very firmly the latter. That in itself is an interesting data-point, because (as discussed in my talk) my reaction towards new technological advances isn’t always one of excitement—quite often it’s one of apprehension, even fear.

I’ve been trying to self-analyse to figure out which kinds of technologies trigger which kind of reaction. I don’t have any firm answers yet, but it’s interesting to note that the three technologies mentioned above (CSS grid, variable fonts, and service workers) are all additions to the core languages of the web—the materials we use to build the web. Frameworks, libraries, build tools, and other such technologies are more like tools than materials. I tend to get less excited about advances in those areas. Sometimes advances in those areas not only fail to trigger excitement, they make me feel overwhelmed and worried about falling behind.

Since figuring out this split between materials and tools, it has helped me come to terms with my gut emotional reaction to the latest technological advances on the web. I think it’s okay that I don’t get excited about everything. And given the choice, I think maybe it’s healthier to be more excited about advances in the materials—HTML, CSS, and JavaScript APIs—than advances in tooling …although, it is, of course, perfectly possible to get equally excited about both (that’s just not something I seem to be able to do).

Another split I’ve noticed is between technologies that directly benefit users, and technologies that directly benefit developers. I think there was a bit of a meta-thread running through the talks at An Event Apart about CSS grid, variable fonts, and service workers: all of those advances allow us developers to accomplish more with less. They’re good for performance, in other words. I get much more nervous about CSS frameworks and JavaScript libraries that allow us to accomplish more, but require the user to download the framework or library first. It feels different when something is baked into browsers—support for CSS features, or JavaScript APIs. Then it feels like much more of a win-win situation for users and developers. If anything, the onus is on developers to take the time and do the work and get to grips with these browser-native technologies. I’m okay with that.

Anyway, all of this helps me understand my feelings at the end of An Event Apart Seattle. I’m fired up and eager to make something with CSS grid, variable fonts, and—of course—service workers.

Ends and means

The latest edition of the excellent History Of The Web newsletter is called The Day(s) The Web Fought Back. It recounts the first time that websites stood up against bad legislation in the form of the Communications Decency Act (CDA), and goes to recount the even more effective use of blackout protests against SOPA and PIPA.

I remember feeling very heartened to see WikiPedia, Google and others take a stand on January 18th, 2012. But I also remember feeling uneasy. In this particular case, companies were lobbying for a cause I agreed with. But what if they were lobbying for a cause I didn’t agree with? Large corporations using their power to influence politics seems like a very bad idea. Isn’t it still a bad idea, even if I happen to agree with the cause?

Cloudflare quite rightly kicked The Daily Stormer off their roster of customers. Then the CEO of Cloudflare quite rightly wrote this in a company-wide memo:

Literally, I woke up in a bad mood and decided someone shouldn’t be allowed on the Internet. No one should have that power.

There’s an uncomfortable tension here. When do the ends justify the means? Isn’t the whole point of having principles that they hold true even in the direst circumstances? Why even claim that corporations shouldn’t influence politics if you’re going to make an exception for net neutrality? Why even claim that free speech is sacrosanct if you make an exception for nazi scum?

Those two examples are pretty extreme and I can easily justify the exceptions to myself. Net neutrality is too important. Stopping fascism is too important. But where do I draw the line? At what point does something become “too important?”

There are more subtle examples of corporations wielding their power. Google are constantly using their monopoly position in search and browser marketshare to exert influence over website-builders. In theory, that’s bad. But in practice, I find myself agreeing with specific instances. Prioritising mobile-friendly sites? Sounds good to me. Penalising intrusive ads? Again, that seems okey-dokey to me. But surely that’s not the point. So what if I happen to agree with the ends being pursued? The fact that a company the size and power of Google is using their monopoly for any influence is worrying, regardless of whether I agree with the specific instances. But I kept my mouth shut.

Now I see Google abusing their monopoly again, this time with AMP. They may call the preferential treatment of Google-hosted AMP-formatted pages a “carrot”, but let’s be honest, it’s an abuse of power, plain and simple.

By the way, I have no doubt that the engineers working on AMP have the best of intentions. We are all pursuing the same ends. We all want a faster web. But we disagree on the means. If Google search results gave preferential treatment to any fast web pages, that would be fine. But by only giving preferential treatment to pages written in a format that they created, and hosted on their own servers, they are effectively forcing everyone to use AMP. I know for a fact that there are plenty of publications who are producing AMP content, not because they are sold on the benefits of the technology, but because they feel strong-armed into doing it in order to compete.

If the ends justify the means, then it’s easy to write off Google’s abuse of power. Those well-intentioned AMP engineers honestly think that they have the best interests of the web at heart:

We were worried about the web not existing anymore due to native apps and walled gardens killing it off. We wanted to make the web competitive. We saw a sense of urgency and thus we decided to build on the extensible web to build AMP instead of waiting for standard and browsers and websites to catch up. I stand behind this process. I’m a practical guy.

There’s real hubris and audacity in thinking that one company should be able to tackle fixing the whole web. I think the AMP team are genuinely upset and hurt that people aren’t cheering them on. Perhaps they will dismiss the criticisms as outpourings of “Why wasn’t I consulted?” But that would be a mistake. The many thoughtful people who are extremely critical of AMP are on the same side as the AMP team when it comes the end-goal of better, faster websites. But burning the web to save it? No thanks.

Ben Thompson goes into more detail on the tension between the ends and the means in The Aggregator Paradox:

The problem with Google’s actions should be obvious: the company is leveraging its monopoly in search to push the AMP format, and the company is leveraging its dominant position in browsers to punish sites with bad ads. That seems bad!

And yet, from a user perspective, the options I presented at the beginning — fast loading web pages with responsive designs that look great on mobile and the elimination of pop-up ads, ad overlays, and autoplaying videos with sounds — sounds pretty appealing!

From that perspective, there’s a moral argument to be made for wielding monopoly power like Google is doing. No doubt the AMP team feel it would be morally wrong for Google not to use its influence in search to give preferential treatment to AMP pages.

Going back to the opening examples of online blackouts, was it morally wrong for companies to use their power to influence politics? Or would it have been morally wrong for them not to have used their influence?

When do the ends justify the means?

Here’s a more subtle example than Google AMP, but one which has me just as worried for the future of the web. Mozilla announced that any new web features they add to their browser will require HTTPS.

The end-goal here is one I agree with: HTTPS everywhere. On the face of it, the means of reaching that goal seem reasonable. After all, we already require HTTPS for sensitive JavaScript APIs like geolocation or service workers. But the devil is in the details:

Effective immediately, all new features that are web-exposed are to be restricted to secure contexts. Web-exposed means that the feature is observable from a web page or server, whether through JavaScript, CSS, HTTP, media formats, etc. A feature can be anything from an extension of an existing IDL-defined object, a new CSS property, a new HTTP response header, to bigger features such as WebVR.

Emphasis mine.

This is a step too far. Again, I am in total agreement that we should be encouraging everyone to switch to HTTPS. But requiring HTTPS in order to use CSS? The ends don’t justify the means.

If there were valid security reasons for making HTTPS a requirement, I would be all for enforcing this. But these are two totally separate areas. Enforcing HTTPS by withholding CSS support is no different to enforcing AMP by withholding search placement. In some ways, I think it might actually be worse.

There’s an assumption in this decision that websites are being made by professionals who will know how to switch to HTTPS. But the web is for everyone. Not just for everyone to use. It’s for everyone to build.

One of my greatest fears for the web is that building it becomes the domain of a professional priesthood. Anything that raises the bar to writing some HTML or CSS makes me very worried. Usually it’s toolchains that make things more complex, but in this case the barrier to entry is being brought right into the browser itself.

I’m trying to imagine future Codebar evenings, helping people to make their first websites, but now having to tell them that some CSS will be off-limits until they meet the entry requirements of HTTPS …even though CSS and HTTPS have literally nothing to do with one another. (And yes, there will be an exception for localhost and I really hope there’ll be an exception for file: as well, but that’s simply postponing the disappointment.)

No doubt Mozilla (and the W3C Technical Architecture Group) believe that they are doing the right thing. Perhaps they think it would be morally wrong if browsers didn’t enforce HTTPS even for unrelated features like new CSS properties. They believe that, in this particular case, the ends justify the means.

I strongly disagree. If you also disagree, I encourage you to make your voice heard. Remember, this isn’t about whether you think that we should all switch to HTTPS—we’re all in agreement on that. This is about whether it’s okay to create collateral damage by deliberately denying people access to web features in order to further a completely separate agenda.

This isn’t about you or me. This is about all those people who could potentially become makers of the web. We should be welcoming them, not creating barriers for them to overcome.

Installing Progressive Web Apps

When I was testing the dConstruct Audio Archive—which is now a Progressive Web App—I noticed some interesting changes in how Chrome on Android offers the “add to home screen” prompt.

It used to literally say “add to home screen.”

Getting the “add to home screen” prompt for https://huffduffer.com/ on Android Chrome. And there’s the “add to home screen” prompt for https://html5forwebdesigners.com/ HTTPS + manifest.json + Service Worker = “Add to Home Screen” prompt. Add to home screen.

Now it simply says “add.”

The dConstruct Audio Archive is now a Progressive Web App

I vaguely remember there being some talk of changing the labelling, but I could’ve sworn it was going to change to “install”. I’ve got to be honest, just having the word “add” doesn’t seem to provide much context. Based on the quick’n’dirty usability testing I did with some co-workers, it just made things confusing. “Add what?” “What am I adding?”

Additionally, the prompt appeared immediately on the first visit to the site. I thought there was supposed to be an added “engagement” metric in order for the prompt to appear; that the user needs to visit the site more than once.

You’d think I’d be happy that users will be presented with the home-screen prompt immediately, but based on the behaviour I saw, I’m not sure it’s a good thing. Here’s what I observed:

  1. The user types the URL archive.dconstruct.org into the address bar.
  2. The site loads.
  3. The home-screen prompt slides up from the bottom of the screen.
  4. The user immediately moves to dismiss the prompt (cue me interjecting “Don’t close that!”).

This behaviour is entirely unsurprising for three reasons:

  1. We web designers and web developers have trained users to dismiss overlays and pop-ups if they actually want to get to the content. Nobody’s going to bother to actually read the prompt if there’s a 99% chance it’s going to say “Sign up to our newsletter!” or “Take our survey!”.
  2. The prompt appears below the “line of death” so there’s no way to tell it’s a browser or OS-level dialogue rather than a JavaScript-driven pop-up from the site.
  3. Because the prompt now appears on the first visit, no trust has been established between the user and the site. If the prompt only appeared on later visits (or later navigations during the first visit) perhaps it would stand a greater chance of survival.

It’s still possible to add a Progressive Web App to the home screen, but the option to do that is hidden behind the mysterious three-dots-vertically-stacked icon (I propose we call this the shish kebab icon to distinguish it from the equally impenetrable hamburger icon).

I was chatting with Andreas from Mozilla at the View Source conference last week, and he was filling me in on how Firefox on Android does the add-to-homescreen flow. Instead of a one-time prompt, they’ve added a persistent icon above the “line of death” (the icon is a combination of a house and a plus symbol).

When a Firefox 58 user arrives on a website that is served over HTTPS and has a valid manifest, a subtle badge will appear in the address bar: when tapped, an “Add to Home screen” confirmation dialog will slide in, through which the web app can be added to the Android home screen.

This kind of badging also has issues (without the explicit text “add to home screen”, the user doesn’t know what the icon does), but I think a more persistently visible option like this works better than the a one-time prompt.

Firefox is following the lead of the badging approach pioneered by the Samsung Internet browser. It provides a plus symbol that, when pressed, reveals the options to add to home screen or simply bookmark.

What does it mean to be an App?

I don’t think Chrome for Android has any plans for this kind of badging, but they are working on letting the site authors provide their own prompts. I’m not sure this is such a good idea, given our history of abusing pop-ups and overlays.

Sadly, I feel that any solution that relies on an unrequested overlay is doomed. That’s on us. The way we’ve turned browsing the web—especially on mobile—into a frustrating chore of dismissing unwanted overlays is a classic tragedy of the commons. We blew it. Users don’t trust unrequested overlays, and I can’t blame them.

For what it’s worth, my opinion is that ambient badging is a better user experience than one-time prompts. That opinion is informed by a meagre amount of testing though. I’d love to hear from anyone who’s been doing more detailed usability testing of both approaches. I assume that Google, Mozilla, and Samsung are doing this kind of testing, and it would be really great to see the data from that (hint, hint).

But it might well be that ambient badging is just too subtle to even be noticed by the user.

On one end of the scale you’ve got the intrusiveness of an add-to-home-screen prompt, but on the other end of the scale you’ve got the discoverability problem of a subtle badge icon. I wonder if there might be a compromise solution—maybe a badge icon that pulses or glows on the first or second visit?

Of course that would also need to be thoroughly tested.

Singapore

I was in Singapore last week. It was most relaxing. Sure, it’s Disneyland With The Death Penalty but the food is wonderful.

chicken rice fishball noodles laksa grilled pork

But I wasn’t just there to sample the delights of the hawker centres. I had been invited by Mozilla to join them on the opening leg of their Developer Roadshow. We assembled in the PayPal offices one evening for a rapid-fire round of talks on emerging technologies.

We got an introduction to Quantum, the new rendering engine in Firefox. It’s looking good. And fast. Oh, and we finally get support for input type="date".

But this wasn’t a product pitch. Most of the talks were by non-Mozillians working on the cutting edge of technologies. I kicked things off with a slimmed-down version of my talk on evaluating technology. Then we heard from experts in everything from CSS to VR.

The highlight for me was meeting Hui Jing and watching her presentation on CSS layout. It was fantastic! Entertaining and informative, it was presented with gusto. I think it got everyone in the room very excited about CSS Grid.

The Singapore stop was the only I was able to make, but Hui Jing has been chronicling the whole trip. Sounds like quite a whirlwind tour. I’m so glad I was able to join in even for a portion. Thanks to Sandra and Ali for inviting me along—much appreciated.

I’ll also be speaking at Mozilla’s View Source in London in a few weeks, where I’ll be talking about building blocks of the Indie Web:

In these times of centralised services like Facebook, Twitter, and Medium, having your own website is downright disruptive. If you care about the longevity of your online presence, independent publishing is the way to go. But how can you get all the benefits of those third-party services while still owning your own data? By using the building blocks of the Indie Web, that’s how!

‘Twould be lovely to see you there.

Container queries

Every single browser maker has the same stance when it comes to features—they want to hear from developers at the coalface.

“Tell us what you want! We’re listening. We want to know which features to prioritise based on real-world feedback from developers like you.”

“How about container quer—”

“Not that.”

I don’t think it’s an exaggeration to say that literally every web developer I know would love to have container queries. If you’ve worked on any responsive project of any size, you’re bound to have bumped up against the problem of only being able to respond to viewport size, rather than the size of the containing element. Without container queries, our design systems can never be truly modular.

But there’s a divide growing between what our responsive designs need to do, and the tools CSS gives us to meet those needs. We’re making design decisions at smaller and smaller levels, but our code asks us to bind those decisions to a larger, often-irrelevant abstraction of a “page.”

But the message from browser makers has consistently been “it’s simply too hard.”

At the Frontend United conference in Athens a little while back, Jonathan gave a whole talk on the need for container queries. At the same event, Serg gave a talk on Houdini.

Now, as I understand it, Houdini is the CSS arm of the extensible web. Just as web components will allow us to create powerful new HTML without lobbying browser makers, Houdini will allow us to create powerful new CSS features without going cap-in-hand to standards bodies.

At this year’s CSS Day there were two Houdini talks. Tab gave a deep dive, and Philip talked specifically about Houdini as a breakthrough for polyfilling.

During the talks, you could send questions over Twitter that the speaker could be quizzed on afterwards. As Philip was talking, I began to tap out a question: “Could this be used to polyfill container queries?” My thumb was hovering over the tweet button at the very moment that Philip said in his talk, “This could be used to polyfill container queries.”

For that happen, browsers need to implement the layout API for Houdini. But I’m betting that browser makers will be far more receptive to calls to implement the layout API than calls for container queries directly.

Once we have that, there are two possible outcomes:

  1. We try to polyfill container queries and find out that the browser makers were right—it’s simply too hard. This certainty is itself a useful outcome.
  2. We successfully polyfill container queries, and then instead of asking browser makers to figure out implementation, we can hand it to them for standardisation.

But, as Eric Portis points out in his talk on container queries, Houdini is still a ways off (by the way, browser makers, that’s two different conference talks I’ve mentioned about container queries, just in case you were keeping track of how much developers want this).

Still, there are some CSS features that are Houdini-like in their extensibility. Custom properties feel like they could be wrangled to help with the container query problem. While it’s easy to think of custom properties as being like Sass variables, they’re much more powerful than that—the fact they can be a real-time bridge between JavaScript and CSS makes them scriptable. Alas, custom properties can’t be used in media queries but maybe some clever person can figure out a way to get the effect of container queries without a query-like syntax.

However it happens, I’d just love to see some movement on container queries. I’m not alone.

I know container queries would revolutionize my design practice, and better prepare responsive design for mobile, desktop, tablet—and whatever’s coming next.