Journal tags: standards

126

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Button types

I’ve been banging the drum for a button type="share" for a while now.

I’ve also written about other potential button types. The pattern I noticed was that, if a JavaScript API first requires a user interaction—like the Web Share API—then that’s a good hint that a declarative option would be useful:

The Fullscreen API has the same restriction. You can’t make the browser go fullscreen unless you’re responding to user gesture, like a click. So why not have button type=”fullscreen” in HTML to encapsulate that? And again, the fallback in non-supporting browsers is predictable—it behaves like a regular button—so this is trivial to polyfill.

There’s another “smell” that points to some potential button types: what functionality do browsers provide in their interfaces?

Some browsers provide a print button. So how about button type="print"? The functionality is currently doable with button onclick="window.print()" so this would be a nicer, more declarative way of doing something that’s already possible.

It’s the same with back buttons, forward buttons, and refresh buttons. The functionality is available through a browser interface, and it’s also scriptable, so why not have a declarative equivalent?

How about bookmarking?

And remember, the browser interface isn’t always visible: progressive web apps that launch with minimal browser UI need to provide this functionality.

Šime Vidas was wondering about button type="copy” for copying to clipboard. Again, it’s something that’s currently scriptable and requires a user gesture. It’s a little more complex than the other actions because there needs to be some way of providing the text to be copied, but it’s definitely a valid use case.

  • button type="share"
  • button type="fullscreen"
  • button type="print"
  • button type="bookmark"
  • button type="back"
  • button type="forward"
  • button type="refresh"
  • button type="copy"

Any more?

Days of style and standards

I first spoke at CSS Day in Amsterdam back in 2016. Well, technically it was the HTML Day preceding CSS Day, when I talked about the A element. I spoke at CSS Day again last year, when I gave a presentation about alternative histories of styling.

One of the advantages to having spoken at the event in the past is that I’m offered a complementary ticket to the event every year. That’s an offer I’ve made the most of.

I’ve just returned from the latest iteration of CSS Day. It was, as always, excellent. I’ve said it before and I’ll say it again, but I just love the way that this event treats CSS with the respect it deserves. I always attend thinking “I know CSS”, but I always leave thinking “I learned a lot about CSS!”

The past few years have been incredibly exciting for the language. We’ve been handed feature after feature, including capabilities we were told just weren’t possible: container queries; :has; cascade layers; view transitions!

As Paul points out in his write-up, there’s been a shift in how these features feel too. In the past, the feeling was “there’s some great stuff arriving and it’ll be so cool once we’ve got browser support.” Now the feeling is finally catching up to the reality: these features are here now. If browser support for an exciting feature is still an issue, wait a few weeks.

Mind you, as Paul also points out, maybe that’s down to the decreased diversity in rendering engines. If a feature ships in Chromium, Webkit, and Gecko, then it’s universally supported. On the one hand, that’s great for developers. But on the other hand, it’s not ideal for the ecosystem of the web.

Anyway, as expected, there was a ton of mind-blowing stuff at CSS Day 2023. Most of the talks were deep dives into specific features. Those deep dives were bookended by big-picture opening and closing talks.

Manuel closed out the show by talking about he’s changing the way he writes and thinks about CSS. I think that’s a harbinger of what’s to come in the next year or so. We’ve had this wonderful burst of powerful new features over the past couple of years; I think what we’ll see next is consolidation. Understanding how these separate pieces play well together is going to be very powerful.

Heck, just exploring all the possibilities of custom properties and :has could be revolutionary. When you add in the architectural implications of cascade layers and container queries, it feels like a whole new paradigm waiting to happen.

That was the vibe of Una’s opening talk too. It was a whistle-stop tour of all the amazing features that have already landed, and some that will be with us very soon.

But Una also highlighted the heartbreaking disparity between the brilliant reality of CSS in browsers today versus how the language is perceived.

Look at almost any job posting for front-end development and you’ll see that CSS still isn’t valued as its own skill. Never mind that you could specialise in a subset of CSS—layout, animation, architecture—and provide 10× value to an organisation, the recruiters are going to play it safe and ask you if you know React.

Rachel Nabors and I were chatting about this gap between the real and perceived value of modern CSS. She astutely pointed out that CSS is kind of a victim of its own resilience. The way you wrote CSS ten years ago still works, and will continue to work. That’s by design. Yes, you can write much better, more resilient CSS today, but if those qualities aren’t valued by an organisation, then you’re casting your pearls before swine.

That said, it’s also true that the JavaScript you wrote ten years ago also continues to work today and will continue to work in the future. So why is it that devs seem downright eager to try the latest JavaScript hotness but are reluctant to use CSS that’s been stable for years?

Or perhaps that’s not an accurate representation of the JavaScript ecosystem. It may well be that the eagerness only extends to libraries and frameworks. There’s reluctance to embrace native JavaScript APIs like Proxy or web components. There’s a weird lack of trust in web standards, and an underserved faith in third-party libraries.

Una speculated that CSS needs a rebranding, like we did back in the days of CSS3, a term which didn’t have any technical meaning but helped galvinise excitement.

I’m not so sure. A successful rebranding today becomes a millstone tomorrow. Again, see CSS3.

Una finished with a call-to-action. Let’s work on building the CSS community.

She compared the number of “front-end” conferences dedicated to JavaScript—over 50 listed on one website—to the number of conferences dedicated to CSS. There’s just one. CSS Day.

Heydon wrote:

It occurs to me there are two types of web conferences: know-your-craft conferences and get-ahead conferences. It’s no coincidence there are simultaneously more get-ahead conferences and more JS-framework conferences.

Una encouraged us to organise more gatherings. It doesn’t need to be a conference. It could just be a local meet-up.

I think that’s an excellent suggestion. As Manuel puts it:

My biggest takeaway: The CSS community needs you!

For me, the value of CSS Day was partly in the excellent content being presented, but it was also in the opportunity to gather with like-minded individuals and realise I’m not alone. It’s also too easy to get gaslit by the grift of “modern web development”, which seems to be built on a foundation of user-hostile priorities that don’t make sense to me—over-engineering, intertwingling of concerns, and developer experience über alles. CSS Day was a welcome reminder to fuck that noise.

Add view transitions to your website

I must admit, when Jake told me he was leaving Google, I got very worried about the future of the View Transitions API.

To recap: Chrome shipped support for the API, but only for single page apps. That had me worried:

If the View Transitions API works across page navigations, it could be the single best thing to happen to the web in years.

If the View Transitions API only works for single page apps, it could be the single worst thing to happen to the web in years.

Well, the multi-page version still hasn’t yet shipped in Chrome stable, but it is available in Chrome Canary behind a flag, so it looks like it’s almost here!

Robin took the words out of my mouth:

Anyway, even this cynical jerk is excited about this thing.

Are you the kind of person who flips feature flags on in nightly builds to test new APIs?

Me neither.

But I made an exception for the View Transitions API. So did Dave:

I think the most telling predictor for the success of the multi-page View Transitions API – compared to all other proposals and solutions that have come before it – is that I actually implemented this one. Despite animations being my bread and butter for many years, I couldn’t be arsed to even try any of the previous generation of tools.

Dave’s post is an excellent step-by-step introduction to using view transitions on your website. To recap:

Enable these two flags in Chrome Canary:

chrome://flags#view-transition
chrome://flags#view-transition-on-navigation

Then add this meta element to the head of your website:

<meta name="view-transition" content="same-origin">

You could stop there. If you navigate around your site, you’ll see that the navigations now fade in and out nicely from one page to another.

But the real power comes with transitioning page elements. Basically, you want to say “this element on this page should morph into that element on that page.” And when I say morph, I mean morph. As Dave puts it:

Behind the scenes the browser is rasterizing (read: making an image of) the before and after states of the DOM elements you’re transitioning. The browser figures out the differences between those two snapshots and tweens between them similar to Apple Keynote’s “Magic Morph” feature, the liquid metal T-1000 from Terminator 2: Judgement Day, or the 1980s cartoon series Turbo Teen.

If those references are lost on you, how about the popular kids book series Animorphs?

Some classic examples would be:

  • A thumbnail of a video on one page morphs into the full-size video on the next page.
  • A headline and snippet of an article on one page morphs into the full article on the next page.

I’ve added view transitions to The Session. Where I’ve got index pages with lists of titles, each title morphs into the heading on the next page.

Again, Dave’s post was really useful here. Each transition needs a unique name, so I used Dave’s trick of naming each transition with the ID of the individual item being linked to.

In the recordings section, for example, there might be a link like this on the index page:

<a href="/recordings/7812" style="view-transition-name: recording-7812">The Banks Of The Moy</a>

Which, if you click on it, takes you to the page with this heading:

<h1><span style="view-transition-name: recording-7812">The Banks Of The Moy</span></h1>

Why the span? Well, like Dave, I noticed some weird tweening happening between block and inline elements. Dave solved the problem with width: fit-content on the block-level element. I just stuck in an extra inline element.

Anyway, the important thing is that the name of the view transition matches: recording-7812.

I also added a view transition to pages that have maps. The position of the map might change from page to page. Now there’s a nice little animation as you move from one page with a map to another page with a map.

thesession.org View Transitions

That’s all good, but I found myself wishing that I could just have those enhancements. Every single navigation on the site was triggering a fade in and out—the default animation. I wondered if there was a way to switch off the default fading.

There is! That default animation is happening on a view transition named root. You can get rid of it with this snippet of CSS:

::view-transition-image-pair(root) {
  isolation: auto;
}
::view-transition-old(root),
::view-transition-new(root) {
  animation: none;
  mix-blend-mode: normal;
  display: block;
}

Voila! Now only the view transitions that you name yourself will get applied.

You can adjust the timing, the easing, and the animation properites of your view transitions. Personally, I was happy with the default morph.

In fact, that’s one of the things I like about this API. It’s another good example of declarative design. I say what I want to happen, but I don’t need to specify the details. I’ll let the browser figure all that out.

That’s what’s got me so excited about this API. Yes, it’s powerful. But just as important, it’s got a very low barrier to entry.

Chris has gathered a bunch of examples together in his post Early Days Examples of View Transitions. Have a look around to get some ideas.

If you like what you see, I highly encourage you to add view transitions to your website now.

“But wait,” I hear you cry, “this isn’t supported in any public-facing browser yet!”

To which, I respond “So what?” It’s a perfect example of progressive enhancement. Adding one meta element and a smidgen of CSS will do absolutely no harm to your website. And while no-one will see your lovely view transitions yet, once browsers do start shipping with support for the API, your site will automatically get better.

Your website will be enhanced. Progressively.

Update: Simon Pieters quite rightly warns against adding view transitions to live sites before the API is done:

in general, using features before they ship in a browser isn’t a great idea since it can poison the feature with legacy content that might break when the feature is enabled. This has happened several times and renames or so were needed.

Good point. I must temper my excitement with pragmatism. Let me amend my advice:

I highly encourage you to experiment with view transitions on your website now.

Innovation

I did an episode of the Clearleft podcast on innovation a while back:

Everyone wants to be innovative …but no one wants to take risks.

The word innovation is often bandied about in an unquestioned positive way. But if we acknowledge that innovation is—by definition—risky, then the exhortations sound less positive.

“We provide innovative solutions for businesses!” becomes “We provide risky solutions for businesses!”

I was reminded of this when I saw the website for the Podcast Standards Project. The original text on the website described the project as:

…a grassroots coalition working to establish modern, open standards, to enable innovation in the podcast industry.

I pushed back on that wording (partly because I’ve seen the word “innovation” used as a smoke screen for user-hostile practices like tracking and surveillance). The wording has since changed to:

…a grassroots coalition dedicated to creating standards and practices that improve the open podcasting ecosystem for both listeners and creators.

That’s better. It’s more precise.

Am I nitpicking? Only if you think that “innovation” and “improvement” are synonyms. I don’t think they are.

Innovation implies change. Improvement implies positive change.

Not all change is positive. Not all innovation is positive.

Innovation goes hand in hand with disruption. Again, disruption involves change. But not necessarily positive change.

Think about the antonyms of change and disruption: stasis and stability. Those words don’t sound very exciting, but in some arenas they’re exactly what you should be aiming for; arenas like infrastructure or standards.

Not to get all pace layers-y here, but it seems to me that every endeavour has a sweet spot for innovation. For some projects, too little innovation is bad. For others, too much innovation is worse.

The trick is knowing which kind of project you’re working on.

(As a side note, I think some people use the word innovation to describe the generative, divergent phase of a design project: “how might we come up with innovative new approaches?” But we already have a word to describe the practice of generating novel and interesting ideas. That word isn’t innovation. It’s creativity.)

Browser history

I woke up today to a very annoying new bug in Firefox. The browser shits the bed in an unpredictable fashion when rounding up single pixel line widths in SVG. That’s quite a problem on The Session where all the sheet music is rendered in SVG. Those thin lines in sheet music are kind of important.

Browser bugs like these are very frustrating. There’s nothing you can do from your side other than filing a bug. The locus of control is very much with the developers of the browser.

Still, the occasional regression in a browser is a price I’m willing to pay for a plurality of rendering engines. Call me old-fashioned but I still value the ecological impact of browser diversity.

That said, I understand the argument for converging on a single rendering engine. I don’t agree with it but I understand it. It’s like this…

Back in the bad old days of the original browser wars, the browser companies just made shit up. That made life a misery for web developers. The Web Standards Project knocked some heads together. Netscape and Microsoft would agree to support standards.

So that’s where the bar was set: browsers agreed to work to the same standards, but competed by having different rendering engines.

There’s an argument to be made for raising that bar: browsers agree to work to the same standards, and have the same shared rendering engine, but compete by innovating in all other areas—the browser chrome, personalisation, privacy, and so on.

Like I said, I understand the argument. I just don’t agree with it.

One reason for zeroing in a single rendering engine is that it’s just too damned hard to create or maintain an entirely different rendering engine now that web standards are incredibly powerful and complex. Only a very large company with very deep pockets can hope to be a rendering engine player. Google. Apple. Heck, even Microsoft threw in the towel and abandoned their rendering engine in favour of Blink and V8.

And yet. Andreas Kling recently wrote about the Ladybird browser. How we’re building a browser when it’s supposed to be impossible:

The ECMAScript, HTML, and CSS specifications today are (for the most part) stellar technical documents whose algorithms can be implemented with considerably less effort and guesswork than in the past.

I’ll be watching that project with interest. Not because I plan to use the brower. I’d just like to see some evidence against the complexity argument.

Meanwhile most other browser projects are building on the raised bar of a shared browser engine. Blisk, Brave, and Arc all use Chromium under the hood.

Arc is the most interesting one. Built by the wonderfully named Browser Company of New York, it’s attempting to inject some fresh thinking into everything outside of the rendering engine.

Experiments like Arc feel like they could have more in common with tools-for-thought software like Obsidian and Roam Research. Those tools build knowledge graphs of connected nodes. A kind of hypertext of ideas. But we’ve already got hypertext tools we use every day: web browsers. It’s just that they don’t do much with the accumulated knowledge of our web browsing. Our browsing history is a boring reverse chronological list instead of a cool-looking knowledge graph or timeline.

For inspiration we can go all the way back to Vannevar Bush’s genuinely seminal 1945 article, As We May Think. Bush imagined device, the Memex, was a direct inspiration on Douglas Engelbart, Ted Nelson, and Tim Berners-Lee.

The article describes a kind of hypertext machine that worked with microfilm. Thanks to Tim Berners-Lee’s World Wide Web, we now have a global digital hypertext system that we access every day through our browsers.

But the article also described the idea of “associative trails”:

Wholly new forms of encyclopedias will appear, ready made with a mesh of associative trails running through them, ready to be dropped into the memex and there amplified.

Our browsing histories are a kind of associative trail. They’re as unique as fingerprints. Even if everyone in the world started on the same URL, our browsing histories would quickly diverge.

Bush imagined that these associative trails could be shared:

The lawyer has at his touch the associated opinions and decisions of his whole experience, and of the experience of friends and authorities.

Heck, making a useful browsing history could be a real skill:

There is a new profession of trail blazers, those who find delight in the task of establishing useful trails through the enormous mass of the common record.

Taking something personal and making it public isn’t a new idea. It was what drove the wave of web 2.0 startups. Before Flickr, your photos were private. Before Delicous, your bookmarks were private. Before Last.fm, what music you were listening to was private.

I’m not saying that we should all make our browsing histories public. That would be a security nightmare. But I am saying there’s a lot of untapped potential in our browsing histories.

Let’s say we keep our browsing histories private, but make better use of them.

From what I’ve seen of large language model tools, the people getting most use of out of them are training them on a specific corpus. Like, “take this book and then answer my questions about the characters and plot” or “take this codebase and then answer my questions about the code.” If you treat these chatbots as calculators for words they can be useful for some tasks.

Large language model tools are getting smaller and more portable. It’s not hard to imagine one getting bundled into a web browser. It feeds on your browsing history. The bigger your browsing history, the more useful it can be.

Except, y’know, for the times when it just make shit up.

Vannevar Bush didn’t predict a Memex that would hallucinate bits of microfilm that didn’t exist.

Negativity bias

When I wrote about my hopes and fears for the View Transitions API, a few people latched on to this sentiment:

If the View Transitions API only works for single page apps, it could be the single worst thing to happen to the web in years.

But I also wrote:

If the View Transitions API works across page navigations, it could be the single best thing to happen to the web in years.

I think it’s worth focusing on that.

Part of the problem is that I gave my hopes and fears an equal airing. But they’re not equally likely.

Take the possibility that the View Transitions API only ships for single page apps, but never ships for regular page transitions. The consequences of that would be big—the API would act as an incentive to build single page apps. But the likelihood of that happening is small. In fact, according to Jake, there’s already an implemention for page transitions in the works at Chrome.

Now what if the View Transitions API ships for pages? The consequences would be equally big—the API would act as an incentive to ditch single page apps and build in a more performant, resilient way. Best of all, the chances of that happening are very large indeed (pretty much a certainty now, given Jake’s update).

So I made a comparison between both of the consequences, which are equally large, but I didn’t make a corresponding comparison of the likelihoods, which are not equally large. Mea culpa!

I should’ve made it clearer that, although the consequences would be really bad if the View Transitions API only supports single page apps, the actual likelihood of that is pretty slim.

That’s probably my negativity bias showing through. (The reason I have a negativity bias is because I am a human. Like, have you ever noticed that if you get feedback on something and 98% of it is positive, you inevitably fixate on the 2%?)

Anyway, the real takeaway here is that if the View Transitions API ships for pages, then the consequences will be really, really good! It would be another nail in the coffin for monolithic JavaScript frameworks slowing down the web. And best of all, the likelihood of this happening is very high!

So let me amend my closing sentences from my previous post:

If the View Transitions API only works for single page apps—which is very unlikely—it could be the single worst thing to happen to the web in years.

If the View Transitions API works across page navigations—which is very, very likely—it could be the single best thing to happen to the web in years.

The glass is half full and it’s only going to get fuller. Time to start planning for a turbo-charged web now.

If you’ve got a website with full page navigations, start thinking about how you’ll be able to apply the View Transitions API as a progressive enhancement to improve the user experience.

If you’ve got a single page app, start thinking about how to ditch a whole bunch of uneccessary dependencies to make a more lightweight foundation of HTML instead of JavaScript, and still get all those slick transitions you get in a single page app!

Time for transitions

I am simultaneously very excited and very nervous about the View Transitions API.

You may know it by its former name—Shared Element Transitions. The name change is very recent.

I’ve been saying for years that some kind of API like this would be brilliant:

I honestly think if browsers implemented this, 80% of client-rendered Single Page Apps could be done as regular good ol’-fashioned websites.

Miriam Suzanne describes the theory of View Transitions succinctly:

Shared-element transitions are designed to work with standard web navigation across multiple page loads, as well as page transitions in ‘single-page’ apps (often called SPAs).

This all sounds brilliant. But the devil is in the implementation details. Right now, the API only works for single page apps. This is totally understandable. For purely pragmatic reasons, single page apps are a simple use case to solve for. It’s going to take a lot more work to get this API to work for multi-page apps (or as we used to call them, websites).

If we get a View Transitions API that works across page navigations, it could potentially turbo-charge the web. It will act as a disencentive to building single page apps—you’d be able to provide swish transitions without sacrificing performance or resilience at the alter of a heavy-handed JavaScript-only architecture.

But if the API only ever works for single page apps (which is the current situation), then it will act as an incentive to make any kind of website into a single page app, regardless of whether it’s actually the appropriate architecture.

That prospect has me very worried indeed.

I’m making my feelings on this known just in case any of the implementators out there are thinking, “Hey, maybe it’s fine that this API only works for single page apps—I’m sure most people would be happy with that.”

If the View Transitions API works across page navigations, it could be the single best thing to happen to the web in years.

If the View Transitions API only works for single page apps, it could be the single worst thing to happen to the web in years.

Update: Jake says:

We’re currently landing code in Chrome for the MPA version.

Very happy to hear that! It’s already in the spec, but it’s good to hear that the implementation isn’t going to lag too much.

Also, read this follow-up.

Supporting logical properties

I wrote recently about making the switch to logical properties over on The Session.

Initially I tried ripping the band-aid off and swapping out all the directional properties for logical properties. After all, support for logical properties is green across the board.

But then I got some reports of people seeing formating issues. These people were using Safari on devices that could no longer update their operating system. Because versions of Safari are tied to versions of the operating system, there was nothing they could do other than switch to using a different browser.

I’ve said it before and I’ll say it again, but as long as this situation continues, Safari is not an evergreen browser. (I also understand that problem lies with the OS architecture—it must be incredibly frustrating for the folks working on WebKit and/or Safari.)

So I needed to add fallbacks for older browsers that don’t support logical properties. Or, to put it another way, I needed to add logical properties as a progressive enhancement.

“No problem!” I thought. “The way that CSS works, I can just put the logical version right after the directional version.”

element {
  margin-left: 1em;
  margin-inline-start: 1em;
}

But that’s not true in this case. I’m not over-riding a value, I’m setting two different properties.

In a left-to-right language like English it’s true that margin-inline-start will over-ride margin-left. But in a right-to-left language, I’ve just set margin-left and margin-inline-start (which happens to be on the right).

This is a job for @supports!

element {
  margin-left: 1em;
}
@supports (margin-inline-start: 1em) {
  element {
    margin-left: unset;
    margin-inline-start: 1em;
  }
}

I’m doing two things inside the @supports block. I’m applying the logical property I’ve just tested for. I’m also undoing the previously declared directional property.

A value of unset is perfect for this:

The unset CSS keyword resets a property to its inherited value if the property naturally inherits from its parent, and to its initial value if not. In other words, it behaves like the inherit keyword in the first case, when the property is an inherited property, and like the initial keyword in the second case, when the property is a non-inherited property.

Now I’ve got three CSS features working very nicely together:

  1. @supports (also known as feature queries),
  2. logical properties, and
  3. the unset keyword.

For anyone using an up-to-date browser, none of this will make any difference. But for anyone who can’t update their Safari browser because they can’t update their operating system, because they don’t want to throw out their perfectly functional Apple device, they’ll continue to get the older directional properties:

I discovered that my Mom’s iPad was a 1st generation iPad Air. Apple stopped supporting that device in iOS 12, which means it was stuck with whatever version of Safari last shipped with iOS 12.

Alternative stylesheets

My website has different themes you can choose from. I don’t just mean a dark mode. These themes all look very different from one another.

I assume that 99.99% of people just see the default theme, but I keep the others around anyway. Offering different themes was originally intended as a way of showcasing the power of CSS, and specifically the separation of concerns between structure and presentation. I started doing this before the CSS Zen Garden was created. Dave really took it to the next level by showing how the same HTML document could be styled in an infinite number of ways.

Each theme has its own stylesheet. I’ve got a very simple little style switcher on every page of my site. Selecting a different theme triggers a page refresh with the new styles applied and sets a cookie to remember your preference.

I also list out the available stylesheets in the head of every page using link elements that have rel values of alternate and stylesheet together. Each link element also has a title attribute with the name of the theme. That’s the standard way to specify alternative stylesheets.

In Firefox you can switch between the specified stylesheets from the View menu by selecting Page Style (notice that there’s also a No style option—very handy for checking your document structure).

Other browsers like Chrome and Safari don’t do anything with the alternative stylesheets. But they don’t ignore them.

Every browser makes a network request for each alternative stylesheet. The request is non-blocking and seems to be low priority, which is good, but I’m somewhat perplexed by the network request being made at all.

I get why Firefox is requesting those stylesheets. It’s similar to requesting a print stylesheet. Even if the network were to drop, you still want those styles available to the user.

But I can’t think of any reason why Chrome or Safari would download the alternative stylesheets.

CSS Day 2022

I was in Amsterdam two weeks ago for CSS Day. It was glorious!

I mean, even without the conference it was just so nice to travel somewhere—by direct train, no less!—and spend some time in a beautiful European city enjoying the good weather.

And of course the conference was great too. I’ve been to CSS Day many times. I love it although technically it should be CSS days now—the conference runs for two days.

It’s an event that really treats CSS for what it is—a powerful language worthy of respect. Also, it has bitterballen.

This time I wasn’t just there as an attendee. I also had the pleasure of opening up the show. I gave a talk called In And Out Of Style, a look at the history—and alternative histories—of CSS.

The video is already online! I’ll get the talk transcribed and publish the text here soon. Meanwhile here’s a list of links to relevant material.

I really, really enjoyed giving this talk. It was so nice to be speaking to a room—or in this case, a church—with real people. I’m done giving talks to my screen. It’s just not the same. Giving this talk made me realise how much I need that feedback from the crowd—the laughs, the nods, maybe even the occasional lightbulb appearing over someone’s head.

As usual, my talk was broad and philosophical in nature. Big-picture pretentious talks are kind of my thing. In this case, I knew that I could safely brush over the details of all the exciting new CSS stuff I mentioned because other talks would be diving deep. And boy, did they ever dive deep!

It’s a cliché to use the adjective “inspiring” to describe a conference, but given all that’s happening in the world of CSS right now, it was almost inevitable that CSS Day would be very inspiring indeed this year. Cascade layers, scoped styles, container queries, custom properties, colour spaces, animation and much much more.

If anything, it was almost too much. If I had one minor quibble with the event it would be that seven talks in a day felt like one talk too many to my poor brain (I think that Marc gets the format just right with Beyond Tellerrand—two days of six talks each). But what a great complaint to have—that there was a glut of great talks!

They’ve already announced the dates for next year’s CSS Day(s): June 8th and 9th, 2023. I strongly suspect that I’ll be there.

Thank you very much to ppk, Krijn, Martijn, and everyone involved in making this year’s CSS Day so good!

Re-evaluating technology

There’s a lot of emphasis put on decision-making: making sure you’re making the right decision; evaluating all the right factors before making a decision. But we rarely talk about revisiting decisions.

I think perhaps there’s a human tendency to treat past decisions as fixed. That’s certainly true when it comes to evaluating technology.

I’ve been guilty of this. I remember once chatting with Mark about something written in PHP—probably something I had written—and I made some remark to the effect of “I know PHP isn’t a great language…” Mark rightly called me on that. The language wasn’t great in the past but it has come on in leaps and bounds. My perception of the language, however, had not updated accordingly.

I try to keep that lesson in mind whenever I’m thinking about languages, tools and frameworks that I’ve investigated in the past but haven’t revisited in a while.

Andy talks about this as the tech tool carousel:

The carousel is like one of those on a game show that shows the prizes that can be won. The tool will sit on there until I think it’s gone through enough maturing to actually be a viable tool for me, the team I’m working with and the clients I’m working for.

Crucially a carousel is circular: tools and technologies come back around for re-evaluation. It’s all too easy to treat technologies as being on a one-way conveyer belt—once they’ve past in front of your eyes and you’ve weighed them up, that’s it; you never return to re-evaluate your decision.

This doesn’t need to be a never-ending process. At some point it becomes clear that some technologies really aren’t worth returning to:

It’s a really useful strategy because some tools stay on the carousel and then I take them off because they did in fact, turn out to be useless after all.

See, for example, anything related to cryptobollocks. It’s been well over a decade and blockchains remain a solution in search of problems. As Molly White put it, it’s not still the early days:

How long can it possibly be “early days”? How long do we need to wait before someone comes up with an actual application of blockchain technologies that isn’t a transparent attempt to retroactively justify a technology that is inefficient in every sense of the word? How much pollution must we justify pumping into our atmosphere while we wait to get out of the “early days” of proof-of-work blockchains?

Back to the web (the actual un-numbered World Wide Web)…

Nolan Lawson wrote an insightful article recently about how he senses that the balance has shifted away from single page apps. I’ve been sensing the same shift in the zeitgeist. That said, both Nolan and I keep an eye on how browsers are evolving and getting better all the time. If you weren’t aware of changes over the past few years, it would be easy to still think that single page apps offer some unique advantages that in fact no longer hold true. As Nolan wrote in a follow-up post:

My main point was: if the only reason you’re using an SPA is because “it makes navigations faster,” then maybe it’s time to re-evaluate that.

For another example, see this recent XKCD cartoon:

“You look around one day and realize the things you assumed were immutable constants of the universe have changed. The foundations of our reality are shifting beneath our feet. We live in a house built on sand.”

The day I discovered that Apple Maps is kind of good now

Perhaps the best example of a technology that warrants regular re-evaluation is the World Wide Web itself. Over the course of its existence it has been seemingly bettered by other more proprietary technologies.

Flash was better than the web. It had vector graphics, smooth animations, and streaming video when the web had nothing like it. But over time, the web caught up. Flash was the hare. The World Wide Web was the tortoise.

In more recent memory, the role of the hare has been played by native apps.

I remember talking to someone on the Twitter design team who was designing and building for multiple platforms. They were frustrated by the web. It just didn’t feel as fully-featured as iOS or Android. Their frustration was entirely justified …at the time. I wonder if they’ve revisited their judgement since then though.

In recent years in particular it feels like the web has come on in leaps and bounds: service workers, native JavaScript APIs, and an astonishing boost in what you can do with CSS. Most important of all, the interoperability between browsers is getting better and better. Universal support for new web standards arrives at a faster rate than ever before.

But developers remain suspicious, still prefering to trust third-party libraries over native browser features. They made a decision about those libraries in the past. They evaluated the state of browser support in the past. I wish they would re-evaluate those decisions.

Alas, inertia is a very powerful force. Sticking with a past decision—even if it’s no longer the best choice—is easier than putting in the effort to re-evaluate everything again.

What’s the phrase? “Strong opinions, weakly held.” We’re very good at the first part and pretty bad at the second.

Just the other day I was chatting with one of my colleagues about an online service that’s available on the web and also as a native app. He was showing me the native app on his phone and said it’s not a great app.

“Why don’t you add the website to your phone?” I asked.

“You know,” he said. “The website’s going to be slow.”

He hadn’t tested this. But years of dealing with crappy websites on his phone in the past had trained him to think of the web as being inherently worse than native apps (even though there was nothing this particular service was doing that required any native functionality).

It has become a truism now. Native apps are better than the web.

And you know what? Once upon a time, that would’ve been true. But it hasn’t been true for quite some time …at least from a technical perspective.

But even if the technologies in browsers have reached parity with native apps, that won’t matter unless we can convince people to revisit their previously-formed beliefs.

The technologies are the easy bit. Getting people to re-evaluate their opinions about technologies? That’s the hard part.

Speaking at CSS Day 2022

I’m very excited about speaking at CSS Day this year. My talk is called In And Out Of Style:

It’s an exciting time for CSS! It feels like new features are being added every day. And yet, through it all, CSS has managed to remain an accessible language for anyone making websites. Is this an inevitable part of the design of CSS? Or has CSS been formed by chance? Let’s take a look at the history—and some alternative histories—of the World Wide Web to better understand where we are today. And then, let’s cast our gaze to the future!

Technically, CSS Day won’t be the first outing for this talk but it will be the in-person debut. I had the chance to give the talk online last week at An Event Apart. Giving a talk online isn’t quite the same as speaking on stage, but I got enough feedback from the attendees that I’m feeling confident about giving the talk in Amsterdam. It went down well with the audience at An Event Apart.

If the description has you intrigued, come along to CSS Day to hear the talk in person. And if you like the subject matter, I’ve put together these links to go with the talk…

Blog posts

Presentations

Proposals (email)

Papers (PDF)

People (Wikipedia)

When should there be a declarative version of a JavaScript API?

I feel like it’s high time I revived some interest in my proposal for button type="share". Last I left it, I was gathering use cases and they seem to suggest that the most common use case for the Web Share API is sharing the URL of the current page.

If you want to catch up on the history of this proposal, here’s what I’ve previously written:

Remember, my proposal isn’t to replace the JavaScript API, it’s to complement it with a declarative option. The declarative option doesn’t need to be as fully featured as the JavaScript API, but it should be able to cover the majority use case. I think this should hold true of most APIs.

A good example is the Constraint Validation API. For the most common use cases, the required attribute and input types like “email”, “url”, and “number” have you covered. If you need more power, reach for the JavaScript API.

A bad example is the Geolocation API. The most common use case is getting the user’s current location. But there’s no input type="geolocation" (or button type="geolocation"). Your only choice is to use JavaScript. It feels heavy-handed.

I recently got an email from Taylor Hunt who has come up with a good litmus test for JavaScript APIs that should have a complementary declarative option:

I’ve been thinking about how a lot of recently-proposed APIs end up having to deal with what Chrome devrel’s been calling the “user gesture/activation budget”, and wondering if that’s a good indicator of when something should have been HTML in the first place.

I think he’s onto something here!

Think about any API that requires a user gesture. Often the documentation or demo literally shows you how to generate a button in JavaScript in order to add an event handler to it in order to use the API. Surely that’s an indication that a new button type could be minted?

The Web Share API is a classic example. You can’t invoke the API after an event like the page loading. You have to invoke the API after a user-initiated event like, oh, I don’t know …clicking on a button!

The Fullscreen API has the same restriction. You can’t make the browser go fullscreen unless you’re responding to user gesture, like a click. So why not have button type="fullscreen" in HTML to encapsulate that? And again, the fallback in non-supporting browsers is predictable—it behaves like a regular button—so this is trivial to polyfill. I should probably whip up a polyfill to demonstrate this.

I can’t find a list of all the JavaScript APIs that require a user gesture, but I know there’s more that I’m just not thinking of. I’d love to see if they’d all fit this pattern of being candidates for a new button type value.

The only potential flaw in this thinking is that some APIs that require a user gesture might also require a secure context (either being served over HTTPS or localhost). But as far as I know, HTML has never had the concept of features being restricted by context. An element is either supported or it isn’t.

That said, there is some prior art here. If you use input type="password" in a non-secure context—like a page being served over HTTP—the browser updates the interface to provide scary warnings. Perhaps browsers could do something similar for any new button types that complement secure-context JavaScript APIs.

2.5.6

The Competition and Markets Authority (CMA) recently published an interim report on their mobile ecosystems market study. It’s well worth reading, especially the section on competition in the supply of mobile browsers:

On iOS devices, Apple bans the use of alternative browser engines – this means that Apple has a monopoly over the supply of browser engines on iOS. It also chooses not to implement – or substantially delays – a wide range of features in its browser engine. This restriction has 2 main effects:

  • limiting rival browsers’ ability to differentiate themselves from Safari on factors such as speed and functionality, meaning that Safari faces less competition from other browsers than it otherwise could do; and
  • limiting the functionality of web apps – which could be an alternative to native apps as a means for mobile device users to access online content – and thereby limits the constraint from web apps on native apps. We have not seen compelling evidence that suggests Apple’s ban on alternative browser engines is justified on security grounds.

That last sentence is a wonderful example of British understatement. Far from protecting end users from security exploits, Apple have exposed everyone on iOS to all of the security issues of Apple’s Safari browser (regardless of what brower the user thinks they are using).

The CMA are soliciting responses to their interim report:

To respond to this consultation, please email or post your submission to:

Email: mobileecosystems@cma.gov.uk

Post: 


Mobile Ecosystems Market Study
Competition and Markets Authority

25 Cabot Square

London

E14 4QZ

Please respond by no later than 5pm GMT on 7 February 2022.

I encourage you to send a response before this coming Monday. This is the email I’ve sent.

Hello,

This response is regarding competition in the supply of mobile browsers and contains no confidential information.

I read your interim report with great interest.

As a web developer and the co-founder of a digital design agency, I could cite many reasons why Apple’s moratorium on rival browser engines is bad for business. But the main reason I am writing to you is as a consumer and a user of Apple’s products.

I own two Apple computing devices: a laptop and a phone. On both devices, I can install apps from Apple’s App Store. But on my laptop I also have the option to download and install an application from elsewhere. I can’t do this on my phone. That would be fine if my needs were met by what’s available in the app store. But clause 2.5.6 of Apple’s app store policy restricts what is available to me as a consumer.

On my laptop I can download and install Mozilla’s Firefox or Google’s Chrome browsers. On my phone, I can install something called Firefox and something called Chrome. But under the hood, they are little more than skinned versions of Safari. I’m only aware of this because I’m au fait with the situation. Most of my fellow consumers have no idea that when they install the app called Firefox or the app called Chrome from the app store on their phone, they are being deceived.

It is this deception that bothers me most.

Kind regards,

Jeremy Keith

To be fair to Apple, this deception requires collusion from Mozilla, Google, Microsoft, and other browser makers. Nobody’s putting a gun to their heads and forcing them to ship skinned versions of Safari that bear only cosmetic resemblance to their actual products.

But of course it would be commercially unwise to forego the app store as a distrubution channel, even if the only features they can ship are superficial ones like bookmark syncing.

Still, imagine what would happen if Mozilla, Google, and Microsoft put their monies where their mouths are. Instead of just complaining about the unjust situation, what if they actually took the financial hit and pulled their faux-browsers from the iOS app store?

If this unjustice is as important as representatives from Google, Microsoft, and Mozilla claim it is, then righteous indignation isn’t enough. Principles without sacrifice are easy.

If nothing else, it would throw the real situation into light and clear up the misconception that there is any browser choice on iOS.

I know it’s not going to happen. I also know I’m being a hypocrite by continuing to use Apple products in spite of the blatant misuse of monopoly power on display. But still, I wanted to plant that seed. What if Microsoft, Google, and Mozilla were the ones who walk away from Omelas.

Today, the distant future

It’s a bit of a cliché to talk about living in the future. It’s also a bit pointless. After all, any moment after the big bang is a future when viewed from any point in time before it.

Still, it’s kind of fun when a sci-fi date rolls around. Like in 2015 when we reached the time depicted in Back To The Future 2, or in 2019 when we reached the time of Blade Runner.

In 2022 we are living in the future of web standards. Again, technically, we’re always living in the future of any past discussion of web standards, but this year is significant …in a very insignificant way.

It all goes back to 2008 and an interview with Hixie, editor of the HTML5 spec at the WHATWG at the time. In it, he mentioned the date 2022 as the milestone for having two completely interoperable implementations.

The far more important—and ambitious—date was 2012, when HTML5 was supposed to become a Candidate Recommendation, which is standards-speak for done’n’dusted.

But the mere mention of the year 2022 back in the year 2008 was too much for some people. Jeff Croft, for example, completely lost his shit (Jeff had a habit of posting angry rants and then denying that he was angry or ranty, but merely having a bit of fun).

The whole thing was a big misunderstanding and soon irrelevant: talk of 2022 was dropped from HTML5 discussions. But for a while there, it was fascinating to see web designers and developers contemplate a year that seemed ludicriously futuristic. Jeff wrote:

God knows where I’ll be in 13 years. Quite frankly, I’ll be pretty fucking disappointed in myself (and our entire industry) if I’m writing HTML in 13 years.

That always struck me as odd. If I thought like that, I’d wonder what the point would be in making anything on the web to begin with (bear in mind that both my own personal website and The Session are now entering their third decade of life).

I had a different reaction to Jeff, as I wrote in 2010:

Many web developers were disgusted that such a seemingly far-off date was even being mentioned. My reaction was the opposite. I began to pay attention to HTML5.

But Jeff was far from alone. Scott Gilbertson wrote an angry article on Webmonkey:

If you’re thinking that planning how the web will look and work 13 years from now is a little bit ridiculous, you’re not alone.

Even if your 2022 ronc-o-matic web-enabled toaster (It slices! It dices! It browses! It arouses!) does ship with Firefox v22.3, will HTML still be the dominant language of web? Given that no one can really answer that question, does it make sense to propose a standard so far in the future?

(I’m re-reading that article in the current version of Firefox: 95.0.2.)

Brian Veloso wrote on his site:

Two-thousand-twenty-two. That’s 14 years from now. Can any of us think that far? Wouldn’t our robot overlords, whether you welcome them or not, have taken over by then? Will the internet even matter then?

From the comments on Jeff’s post, there’s Corey Dutson:

2022: God knows what the Internet will look like at that point. Will we even have websites?

Dan Rubin, who has indeed successfully moved from web work to photography, wrote:

I certainly don’t intend to be doing “web work” by that time. I’m very curious to see where the web actually is in 14 years, though I can’t imagine that HTML5 will even get that far; it’ll all be obsolete before 2022.

Joshua Works made a prediction that’s worryingly close to reality:

I’ll be surprised if website-as-HTML is still the preferred method for moving around the tons of data we create, especially in the manner that could have been predicted in 2003 or even today. Hell, iPods will be over 20 years old by then and if everything’s not run as an iPhone App, then something went wrong.

Someone with the moniker Grand Caveman wrote:

In 2022 I’ll be 34, and hopefully the internet will be obsolete by then.

Perhaps the most level-headed observation came from Jonny Axelsson:

The world in 2022 will be pretty much like the world in 2009.

The world in 2009 is pretty much like 1996 which was pretty much like the world in 1983 which was pretty much like the world in 1970. Some changes are fairly sudden, others are slow, some are dramatic, others subtle, but as a whole “pretty much the same” covers it.

The Web in 2022 will not be dramatically different from the Web in 2009. It will be less hot and it will be less cool. The Web is a project, and as it succeeds it will fade out of our attention and into the background. We don’t care about things when they work.

Now that’s a sensible perspective!

So who else is looking forward to seeing what the World Wide Web is like in 2036?

I must remember to write a blog post then and link back to this one. I have no intention of trying to predict the future, but I’m willing to bet that hyperlinks will still be around in 14 years.

Speaking of long bets…

Faulty logic

I’m a fan of logical properties in CSS. As I wrote in the responsive design course on web.dev, they’re crucial for internationalisation.

Alaa Abd El-Rahim has written articles on CSS tricks about building multi-directional layouts and controlling layout in a multi-directional website. Not having to write separate stylesheets—or even separate rules—for different writing modes is great!

More than that though, I think understanding logical properties is the best way to truly understand CSS layout tools like grid and flexbox.

It’s like when you’re learning a new language. At some point your brain goes from translating from your mother tongue into the other language, and instead starts thinking in that other language. Likewise with CSS, as some point you want to stop translating “left” and “right” into “inline-start” and “inline-end” and instead start thinking in terms of inline and block dimensions.

As is so often the case with CSS, I think new features like these are easier to pick up if you’re new to the language. I had to unlearn using floats for layout and instead learn flexbox and grid. Someone learning layout from scatch can go straight to flexbox and grid without having to ditch the cognitive baggage of floats. Similarly, it’s going to take time for me to shed the baggage of directional properties and truly grok logical properties, but someone new to CSS can go straight to logical properties without passing through the directional stage.

Except we’re not quite there yet.

In order for logical properties to replace directional properties, they need to be implemented everywhere. Right now you can’t use logical properties inside a media query, for example:

@media (min-inline-size: 40em)

That wont’ work. You have to use the old-fashioned syntax:

@media (min-width: 40em)

Now you could rightly argue that in this instance we’re talking about the physical dimensions of the viewport. So maybe width and height make more sense than inline and block.

But then take a look at how the syntax for container queries is going to work. First you declare the axis that you want to be contained using the syntax from logical properties:

main {
  container-type: inline-size;
}

But then when you go to declare the actual container query, you have to use the corresponding directional property:

@container (min-width: 40em)

This won’t work:

@container (min-inline-size: 40em)

I kind of get why it won’t work: the syntax for container queries should match the syntax for media queries. But now the theory behind disallowing logical properties in media queries doesn’t hold up. When it comes to container queries, the physical layout of the viewport isn’t what matters.

I hope that both media queries and container queries will allow logical properties sooner rather than later. Until they fall in line, it’s impossible to make the jump fully to logical properties.

There are some other spots where logical properties haven’t been fully implemented yet, but I’m assuming that’s a matter of time. For example, in Firefox I can make a wide data table responsive by making its container side-swipeable on narrow screens:

.table-container {
  max-inline-size: 100%;
  overflow-inline: auto;
}

But overflow-inline and overflow-block aren’t supported in any other browsers. So I have to do this:

.table-container {
  max-inline-size: 100%;
  overflow-x: auto;
}

Frankly, mixing and matching logical properties with directional properties feels worse than not using logical properties at all. The inconsistency is icky. This feels old-fashioned but consistent:

.table-container {
  max-width: 100%;
  overflow-x: auto;
}

I don’t think there are any particular technical reasons why browsers haven’t implemented logical properties consistently. I suspect it’s more a matter of priorities. Fully implementing logical properties in a browser may seem like a nice-to-have bit of syntactic sugar while there are other more important web standard fish to fry.

But from the perspective of someone trying to use logical properties, the patchy rollout is frustrating.

Publishing The State Of The Web

Back in April I gave a talk at An Event Apart Spring Summit. The talk was called The State Of The Web, and I’ve published the transcript. I’ve also published the video.

I put a lot of work into this talk and I think it paid off. I wrote about preparing the talk. I also wrote about recording it. I also published links related to the talk. It was an intense process, but a rewarding one.

I almost called the talk The Overview Effect. My main goal with the talk was to instil a sense of perspective. Hence the references to the famous Earthrise photograph.

On the one hand, I wanted the audience to grasp just how far the web has come. So the first half of the talk is a bit of a trip down memory lane, with a constant return to just how much we can accomplish in browsers today. It’s all very positive and upbeat.

Then I twist the knife. Having shown just how far we’ve progressed technically, I switch gears the moment I say:

The biggest challenges facing the World Wide Web today are not technical challenges.

Then I dive into those challenges, as I see them. It turns out that technical challenges would be preferable to the seemingly intractable problems of today’s web.

I almost wish I could’ve flipped the order: talk about the negative stuff first but then finish with the positive. I worry that the talk could be a bit of a downer. Still, I tried to finish on an optimistic note.

I won’t spoil it any more for you. Watch the video or have a read of The State Of The Web.

BBC feedback

I just filled out this form on the BBC website. Here’s what I wrote, based on this open letter to the BCC Upper Management and Editorial Staff.

What is your complaint about?

BBC website or apps

Which website or app is your complaint about?

BBC News website

Please give the URL, or name of the app

https://www.bbc.co.uk/news/uk-england-57853385

Are you contacting us about a previous complaint?

No

Select the best category to describe your complaint

Standards of interviewing/presenting

What is the subject of your complaint?

Innacurate reporting and unreliable source

Please enter your complaint

The article is based on a single self selected study of 80 individuals sourced from Get The L Out, a group who, prior to the survey, were already united by anti-trans views.

This study breaks the BBC’s own guidelines about using surveys as sources for claims in coverage, as it is self-selected, with a small sample size and a clear bias held by those self-selected to respond.

The article dangerously frames this as a widespread issue, whilst simultaneously acknowledging that there is no actual evidence to that effect outside of isolated claims and cherry picked individual cases.

The article routinely implies that transgender women are not women, uncritically quoting people who call transgender women men without at any point clarifying that this is ignoring their legal status as women in the UK.

Stakeholders of styling

When I wrote about the new accent-color property in CSS, I pondered how much control a web developer should have over styling form controls:

Who are we to make that decision? Shouldn’t the user’s choice take primacy over our choices?

But then again, where do we draw the line? We’re allowed over-ride link colours. We’re allowed over-ride font choices.

Ultimately, I came down on the side of granting authors more control:

If developers don’t get a standardised way to customise native form controls, they’ll just recreate their own over-engineered versions.

This question of “who gets to decide?” used to be much more prevelant in the early days of the web. One way to think about this is that there are three stakeholders involved in the presentation of a web page:

  1. The author of the page. “Author” is spec-speak for designer or developer.
  2. The user.
  3. The browser, or user agent. A piece of software tries to balance the needs of both author and user. But, as the name implies, the user takes precedence.

These days we tend to think of web design a single-stakeholder undertaking. The author decides how something should be presented and then executes that decision using CSS.

But as Eric once said, every line of you CSS you write is a suggestion to the browser. That’s not how we think about CSS though. We think of CSS like a series of instructions rather than suggestions. Never mind respecting the user’s preferences; one of the first things we do is reset all the user agent’s styles.

In the early days of the web, more consideration was given to the idea of style suggestions rather than instructions. Heck, users could always over-ride any of your suggestions with their own user stylesheet. These days, users would need to install a browser extension to do the same thing.

The first proposal for CSS had a concept called “influence”:

h2.font.size = 20pt 40%

Here, the requested influence is reduced to 40%. If a style sheet later in the cascade also requests influence over h2.font.size, up to 60% can be granted. When the document is rendered, a weighted average of the two requests is calculated, and the final font size is determined.

I think the only remnant of “influence” left in CSS is accidental. It’s in the specificity of selectors …and the !important declaration.

I think it’s a shame that user stylesheets are no longer a thing. But I get why they were dropped from browsers. They date from a time when it was mostly nerds using the web, before “regular folks” came on board. I understand why it became a little-used feature, suitable for being dropped. But the principle of it still rankles slightly.

But in recent years there has been a slight return to the multi-stakeholder concept of styling websites. Thanks to prefers-reduced-motion and prefers-color-scheme, a responsible author can choose to bow to the wishes of the user.

I was reminded of this when I added a dark mode to my website:

Y’know, when I first heard about Apple adding dark mode to their OS—and also to CSS—I thought, “Oh, great, Apple are making shit up again!” But then I realised that, like user style sheets, this is one more reminder to designers and developers that they don’t get the last word—users do.

Accent all areas

Whenever a new version of Chrome comes out, there’s an accompanying blog post listing what’s new. Chrome 93 just came out and, sure enough, Pete has written a blog post about it.

But what I think is the most exciting addition to the browser isn’t listed.

What is this feature that’s got me so excited?

Okay, I’ve probably oversold it now because actually, it looks like a rather small trivial addition. It’s the accent-color property in CSS.

Up until now, accent colour was controlled by the operating system. If you’re on a Mac, go to “System Preferences” and then “General”. There you’ll see an option to change your accent colour. Try picking a different colour. You’ll see that change cascade down into the other form fields in that preference pane: checkboxes, radio buttons, and dropdowns.

Your choice will also cascade down into web pages. Any web page that uses native checkboxes, radio buttons and other interface elements will inherit that colour.

This is how interface elements are supposed to work. The browser inherits the look’n’feel of the inputs from the operating system.

That’s the theory anyway. In practice, form elements—such as dropdowns—can look different from browser to browser, something that shouldn’t be happening if the browsers are all inheriting from the operating system.

Anyway, it’s probably this supposed separation of responsibility between browser and operating system which has led to the current situation with form fields and CSS. Authors can style form fields up to a point, but there’s always a line that you don’t get to cross.

The accent colour of a selected radio button or a checkbox has historically been on the other side of that line. You either had to accept that you couldn’t change the colour, or you had to make your own checkbox or radio button interface. You could use CSS to hide the native element and replace it with an image instead.

That feels a bit over-engineered and frankly kind of hacky. It reminds me of the bad old days of image replacement for text before we had web fonts.

Now, with the accent-color property in CSS, authors can over-ride the choice that the user has set at the operating system level.

On the one hand, this doesn’t feel great to me. Who are we to make that decision? Shouldn’t the user’s choice take primacy over our choices?

But then again, where do we draw the line? We’re allowed over-ride link colours. We’re allowed over-ride font choices.

Ultimately I think it’s a good thing that authors can now specify an accent colour. What makes me think that is the behaviour that authors have shown if they don’t have this ability—they do it anyway, and in a hackier manner. This is why I think the work of the Open UI group is so important. If developers don’t get a standardised way to customise native form controls, they’ll just recreate their own over-engineered versions.

The purpose of Open UI to the web platform is to allow web developers to style and extend built-in web UI controls, such as select dropdowns, checkboxes, radio buttons, and date/color pickers.

Trying to stop developers from styling checkboxes and radio buttons is like trying to stop teenagers from having sex. You might as well accept that it’s going to happen and give them contraception so they can at least do it safely.

So I welcome this new CSS condom.

You can see accent-color in action in this demo. Change the value of the accent-color property to see the form fields update:

:root {
  accent-color: rebeccapurple;
}

Applying it at the document level like that will make it universal, but you can also use the property on an element-by-element basis using whatever selector you want.

That demo works in Chrome and Edge 93, the current release. It also works in Firefox 92, which literally just landed (like as I was writing this blog post, support for accent-color magically arrived!).

As for Safari, well, who knows? If Apple published a roadmap, then developers would have a clue when to expect a property like this to land. But we mere mortals cannot be trusted with such important hush-hush information.

In the meantime, keep an eye on Can I Use. And lack of support on one browser is no reason not to use accent-color anyway. It’s a progressive enhancement. Add it to your CSS today and it will work in more browsers in the future.