Edge Goes Chromium: What Does it Mean for Front-End Developers?

In December 2018, Microsoft announced that Edge would adopt Chromium, the open source project that powers Google Chrome. Many within the industry reacted with sadness at the loss of browser diversity. Personally, I was jubilant. An official release date has yet to be announced, but it will be at some point this year. With its release, a whole host of HTML, JavaScript and CSS features will have achieved full cross-browser support.

The preview build is now available for Windows, and coming soon for Mac.

Not so long ago, I penned an article titled “The Long Slow Death of Internet Explorer.” Some of us are lucky enough have abandoned that browser already. But it wasn’t the only thing holding us back. Internet Explorer was the browser we all hated and Edge was meant to be its much-improved replacement. Unfortunately, Edge itself was quite the laggard. EdgeHTML is a fork of Trident, the engine that powered Internet Explorer. Microsoft significantly under-invested in Edge. The apple didn’t fall far from the tree. Edge’s User Voice website was a nice idea, allowing developers to vote for which features they wanted to be implemented. Unfortunately, as Dave Rupert put it, voting on the site was “like throwing coins in a wishing well.” The most requested features were left unimplemented for years.

There are a lot of features that pre-Chromium Edge doesn’t currently support but are available in other modern browsers and, once they’ve made the switch, we’ll be able to use them. Many of them can’t be polyfilled or worked around, so this release is a big deal.

Features we can look forward to using

So just what are those features, exactly? Let’s outline them right here and start to get excited about all the new things we’ll be able to do.

Custom Elements and Shadow DOM

Together, custom elements and shadow DOM allow developers to define custom, reusable and encapsulated components. A lot of people were asking for this one. People have been voting for its implementation since 2014, and we’re finally getting it.

HTML details and summary elements

The <details> and <summary> elements are part of HTML5 and have been supported since 2011 in Chrome. Used together, the elements generate a simple widget to show and hide content. While it is trivial to implement something similar using JavaScript, the <details> and <summary> elements work even when JavaScript is disabled or has failed to load.

See the Pen
by CSS GRID (@cssgrid)
on CodePen.

Javascript Font Loading API

This one means a lot to some people. All modern browsers now support the CSS font-display property. However, you still might want to load your fonts with JavaScript. Font-loading monomaniac Zach Leatherman has an explainer of why you might want to load fonts with JavaScript even though we now have broad support for font-display. Ditching polyfills for this API is important because this JavaScript is, according to Zach:

[…] usually inlined in the critical path. The time spent parsing and executing polyfill JavaScript is essentially wasted on browsers that support the native CSS Font Loading API.”

In an article from 2018, Zach lamented:

[…] browser-provided CSS Font Loading API has pretty broad support and has been around for a long time but is confoundedly still missing from all available versions of Microsoft Edge.”

No longer!

JavaScript flat and flatMap

Most easily explained with a code snippet, flat() is useful when you have an array nested inside another array.

const things = ['thing1', 'thing2', ['thing3', ['thing4']]]
const flattenedThings = things.flat(2); // Returns ['thing1', 'thing2', 'thing3', 'thing4']

As its name suggests, flatMap() is equivalent to using both the map() method and flat().

These methods are also supported in Node 11. 🎉

JavaScript TextEncoder and TextDecoder

TextEncoder and TextDecoder are part of the encoding spec. They look to be useful when working with streams.

JavaScript Object rest and object spread

These are just like rest and spread properties for arrays.

const obj1 = { a: 100, b: 2000
} const obj2 = { c: 11000, d: 220
} const combinedObj = {...obj1, ...obj2} // {a: 100, b: 2000, c: 11000, d: 220}

JavaScript modules: dynamic import

Using a function-like syntax, dynamic imports allow you to lazy-load ES modules when a user needs them.

button.addEventListener("click", function() { import("./myModule.js").then(module => module.default());

CSS background-blend-mode property

background-blend-mode brings Photoshop style image manipulation to the web.

CSS prefers-reduced-motion media query

I can’t help feeling that not making people feel sick should be the default of a website, particularly as not all users will be aware that this setting exists. As animation on the web becomes more common, it’s important to recognize that animation can cause causes dizziness, nausea and headaches for some users.

CSS caret-color property

Admittedly a rather trivial feature, and one that could have safely and easily been used as progressive enhancement. It lets you style the blinking cursor in text input fields.

8-digit hex color notation

It’s nice to have consistency in a codebase. This includes sticking to either
the RGB, hexadecimal or HSL color format. If your preferred format is hex, then you had a problem because it required a switch to rgba() any time you needed to define transparency. Hex can now include an alpha (transparency) value. For example, #ffffff80 is equivalent to rgba(255, 255, 255, .5). Arguably, it’s not the most intuitive color format and has no actual benefit over rgba().

Intrinsic sizing

I’ve not seen as much hype or excitement for intrinsic sizing as some other new CSS features, but it’s the one I’m personally hankering for the most. Intrinsic sizing determines sizes based on the content of an element and introduces three new keywords into CSS: min-content, max-content and fit-content(). These keywords can be used most places that you would usually use a length, like height, width, min-width, max-width, min-height, max-height, grid-template-rows, grid-template-columns, and flex-basis.

CSS text-orientation property

Used in conjunction with the writing-mode property, text-orientation, specifies the orientation of text, as you might expect.

See the Pen
text-orientation: upright
by CSS GRID (@cssgrid)
on CodePen.

CSS :placeholder-shown pseudo-element

placeholder-shown was even available in Internet Explorer, yet somehow never made it into Edge… until now. UX research shows that placeholder text should generally be avoided. However, if you are using placeholder text, this is a handy way to apply styles conditionally based on whether the user has entered any text into the input.

CSS place-content property

place-content is shorthand for setting both the align-content and justify-content.

See the Pen
by CSS GRID (@cssgrid)
on CodePen.

CSS will-change property

The will-change property can be used as a performance optimization, informing the browser ahead of time that an element will change. Pre-Chromium Edge was actually good at handling animations performantly without the need for this property, but it will now have full cross-browser support.

CSS all property

https://css-tricks.com/almanac/properties/a/all/”>all is a shorthand for setting all CSS properties at once.

For example, setting button { all: unset; } is equivalent to:

button { background: none; border: none; color: inherit; font: inherit; outline: none; padding: 0;

Sadly, though, the revert keyword still hasn’t been implemented anywhere other than Safari, which somewhat limits the mileage we can get out of the all property.

CSS Shapes and Clip Path

Traditionally, the web has been rectangle-centric. It has a box model, after all. While we no longer need floats for layout, we can use them creatively for wrapping text around images and shapes with the shape-outside property. This can be combined with the clip-path property, which brings the ability to display an image inside a shape.

Clippy is an online clip-path editor

CSS :focus-within pseudo-class

If you want to apply special styles to an entire form when any one of its inputs are in focus, then :focus-within is the selector for you.

CSS contents keyword

This is pretty much essential if you’re working with CSS grid. This had been marked as “not planned” by Edge, despite 3,920 votes from developers.

For both flexbox and grid, only direct children become flex items or grid items, respectively. Anything that is nested deeper cannot be placed using flex or grid-positioning. In the words of the spec, when display: contents is applied to a parent element, “the element must be treated as if it had been replaced in the element tree by its contents,” allowing them to be laid out with a grid or with flexbox. Chris goes into a more thorough explanation that’s worth checking out.

There are, unfortunately, still some bugs with other browser implementations that affect accessibility.

The future holds so much more promise

We’ve only looked at features that will be supported by all modern browsers when Edge makes the move to Chromium. That said, the death of legacy Edge also makes a lot of other features feel a lot closer. Edge was the only browser dragging its feet on the Web Animation API and that showed no interest in any part of the Houdini specs, for example.

Credit: https://ishoudinireadyyet.com

The impact on browser testing

Testing in BrowserStack (left) and various browser apps on my iPhone (right)

Of course, the other huge plus for web developers is less testing. A lot of neglected Edge during cross-browser testing, so Edge users were more likely to have a broken experience. This was the main reason Microsoft decided to switch to Chromium. If your site is bug-free in one Chromium browser, then it’s probably fine in all of them. In the words of the Edge team, Chromium will provide “better web compatibility for our customers and less-fragmentation of the web for all web developers.” The large variety of devices and browsers makes browser testing one of the least enjoyable tasks that we’re responsible for as front-end developers. Edge will now be available for macOS users which is great for the many of us who work on a Mac. A subscription to BrowserStack will now be slightly less necessary.

Do we lose anything?

To my knowledge, the only feature that was supported everywhere except Chrome is SVG color fonts, which will no longer work in the Edge browser. Other color font formats (COLR, SBIX, CBDT/CBLC) will continue to work though.

What about other browsers?

Admittedly, Edge wasn’t the last subpar browser. All the features in this article are unsupported in Internet Explorer, and always will be. If you have users in Russia, you’ll need to support Yandex. If you have users in Africa, you’ll need to support Opera Mini. If you have users in China, then UC and QQ will be important to test against. If you don’t have these regional considerations, there’s never been a better time to ditch support for Internet Explorer and embrace the features the modern web has to offer. Plenty of PC users have stuck with Internet Explorer purely out of habit. Hopefully, a revamped Edge will be enough to tempt them away. An official Microsoft blog entry titled “The perils of using Internet Explorer as your default browser” concluded that, “Internet Explorer is a compatibility solution…developers by and large just aren’t testing for Internet Explorer these days.” For its remaining users, the majority of the web must look increasingly broken. It’s time to let it die.

Is Google a megalomaniac?

Life is about to get easier for web developers, yet the response to the Microsoft’s announcement was far from positive. Mozilla, for one, had a stridently pessimistic response, which accused Microsoft of “officially giving up on an independent shared platform for the internet.” The statement described Google as having “almost complete control of the infrastructure of our online lives” and a “monopolistic hold on unique assets.” It concluded that “ceding control of fundamental online infrastructure to a single company is terrible.”

Many have harked back to the days of IE6, the last time a browser achieved such an overwhelming market share. Internet Explorer, having won the browser war, gave in to total stagnation. Chrome, by contrast, ceaselessly pushes new features. Google participates actively with the web standards bodies the W3C and the WHATWG. Arguably though, it has an oversized influence in these bodies and the power to dictate the future shape of the web. Google Developer Relations does have a tendency to hype features that have shipped only in Chrome.

From competition to collaboration

Rather than being the new IE, Edge can help innovate the web forward. While it fell behind in many areas, it did lead the way for CSS grid, CSS exclusions, CSS regions and the new HTML imports spec. In a radical departure from historical behavior, Microsoft have become one of the world’s largest supporters of open source projects. That means all major browsers are now open source. Microsoft have stated that they intend to become a significant contributor to Chromium — in fact, they’ve already racked up over 300 merges. This will help Edge users, but will also benefit users of Chrome, Opera, Brave, and other Chromium-based browsers.

The post Edge Goes Chromium: What Does it Mean for Front-End Developers? appeared first on CSS-Tricks.

Control the Internet With Chrome Extensions!

As a web UI developer and designer, there are countless things to learn and only so many hours in the day. There are topics I’ve purposefully avoided, like mobile and offline application development because, at some point, you have to draw a line somewhere in the millions of shiny new topics and get some work done. One of the areas I’ve avoided in the past is browser extension development. I didn’t understand how they worked, what the development environment was, or how permissions interacted with overriding pages because, frankly, I didn’t think I was interested.

Then one day, my very talented designer/developer friend Natalie Schoch asked me to get her Chrome Extension across the finish line. She had the front-end prototyped, but needed some help plugging in the data set and with interactive JavaScript. The project is called Wordsmith and it’s out now at the Chrome Extension Store. It’s a free and aesthetically pleasing way to learn new vocabulary as you browse the web. The extension surfaces a new vocabulary word, along with its definition and synonyms in each new tab.

Anyway, enough plugging the new thing we made and on to the fun of figuring out Chrome Extensions!

Continue reading Control the Internet With Chrome Extensions!

New mobile Chrome feature would disable scripts on slow connections

This is a possible upcoming feature for mobile Chrome:

If a Data Saver user is on a 2G-speed or slower network according to the NetInfo API, Chrome disables scripts and sends an intervention header on every resource request. Users are shown a UI at the bottom of the screen indicating the page has been modified to save data. Users can enable scripts on the page by tapping “Show original” in the UI.

And the people shout: progressive enhancement!

Jeremy Keith:

An excellent idea for people in low-bandwidth situations: automatically disable JavaScript. As long as the site is built with progressive enhancement, there’s no problem (and if not, the user is presented with the choice to enable scripts).

Power to the people!

George Burduli reports:

This is huge news for developing countries where mobile data packets may cost a lot and are not be affordable to all. Enabling NoScript by default will make sure that users don’t burn through their data without knowledge. The feature will probably be available in the Chrome 69, which will also come with the new Material Design refresh.

The post New mobile Chrome feature would disable scripts on slow connections appeared first on CSS-Tricks.

A native lazy load for the web platform

A new Chrome feature dubbed “Blink LazyLoad” is designed to dramatically improve performance by deferring the load of below-the-fold images and third-party <iframe>s.

The goals of this bold experiment are to improve the overall render speed of content that appears within a user’s viewport (also known as above-the-fold), as well as, reduce network data and memory usage. ✨

👨‍🏫 How will it work?

It’s thought that temporarily delaying less important content will drastically improve overall perceived performance.

If this proposal is successful, automatic optimizations will be run during the load phase of a page:

  • Images and iFrames will be analysed to gauge importance.
  • If they’re seen to be non-essential, they will be deferred, or not loaded at all:
    • Deferred items will only be loaded if the user has scrolled to the area nearby.
    • A blank placeholder image will be used until an image is fetched.

The public proposal has a few interesting details:

  • LazyLoad is made up of two different mechanisms: LazyImages and LazyFrames.
  • Deferred images and iFrames will be loaded when a user has scrolled within a given number of pixels. The number of pixels will vary based on three factors:
    • If it is an iFrame or an image
    • Data Saver is enabled or disabled
    • The “effective connection type”
  • Once the browser has established that an image is located below the fold, it will issue a range request to fetch the first few bytes of an image to establish its dimensions. The dimensions will then be used to create a placeholder.

The lazyload attribute will allow authors to specify which elements should or should not be lazy loaded. Here’s an example that indicates that this content is non-essential:

<iframe src="ads.html" lazyload="on"></iframe>

There are three options:

  • on – Indicates a strong preference to defer fetching until the content can be viewed.
  • off – Fetch this resource immediately, regardless of view-ability.
  • auto – Let the browser decide (has the same effect as not using the lazyload attribute at all).

🔒 Implementing a secure LazyLoad policy

Feature policy: LazyLoad will provide a mechanism that allows authors to force opting in or out of LazyLoad functionality on a per-domain basis (similar to how Content Security Policies work). There is a yet-to-be-merged pull request that describes how it might work.

🤔 What about backwards compatibility?

At this point, it is difficult to tell if these page optimizations could cause compatibility issues for existing sites.

Third party iFrames are used for a large number of purposes like ads, analytics or authentication. Delaying or not loading a crucial iFrame (because the user never scrolls that far) could have dramatic unforeseeable effects. Pages that rely on an image or iFrame having been loaded and present when onLoad fires could also face significant issues.

These automatic optimizations could silently and efficiently speed up Chrome’s rendering speed without any notable issues for users. The Google team behind the proposal are carefully measuring the performance characteristics of LazyLoad’s effects through metrics that Chrome records.

💻 Enabling LazyLoad

At the time of writing, LazyLoad is only available in Chrome Canary, behind two required flags:

  • chrome://flags/#enable-lazy-image-loading
  • chrome://flags/#enable-lazy-frame-loading

Flags can be enabled by navigating to chrome://flags in a Chrome browser.

📚 References and materials

  • LazyLoad public proposal
  • HTML Living Standard Pull Request – lazyload attribute
  • HTTP Range Requests
  • Chrome Platform Status – Feature policy: lazyload
  • LazyLoad Frames was merged into Chromium (minutes after publishing)
  • Calibre performance monitoring

👋 In closing

As we embark on welcoming the next billion users to the web, it’s humbling to know that we are only just getting started in understanding the complexity of browsers, connectivity, and user experience.

The post A native lazy load for the web platform appeared first on CSS-Tricks.

Better rendering for variable fonts

I was messing around with a variable font the other day and noticed this weird rendering issue in the latest version of Chrome where certain parts of letterforms were clipping into each other in a really weird way. Thankfully, though, Stephen Nixon has come to the rescue with a temporary hack to fix the issue which using a text-shadow on the text that’s using the variable font:

.variable-font { text-shadow: 0 0 0 #000; /* text color goes last here */

Once you do that, you shouldn’t be able to see those weird clip marks in the letterforms anymore. Yeah, it feels pretty hacky but I’m sure this rendering bug will be fixed relatively soon. It doesn’t look like it affects other browsers, as far as I can tell.

Direct Link to Article — Permalink

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Careful Now

Tom Warren’s “Chrome is turning into the new Internet Explorer 6” for The Verge has a title that, to us front-end web developers, suggests that Chrome is turning into a browser far behind in technology and replete with tricky bugs. Aside from the occasional offhand generic, “Chrome is getting so bad lately,” comments you hear, we know that’s not true. Chrome often leads the pack for good web tech.

Instead, it’s about another equally concerning danger: developers building sites specifically for Chrome. In theory, that’s not really a thing, because if you build a website with web standards (of which there isn’t really much of an alternative) it’ll work in Chrome like any other modern web browser. But it is a thing if you build the site to somehow block other browsers and only allow Chrome. Warren:

Google has been at the center of a lot of “works best with Chrome” messages we’re starting to see appear on the web. Google Meet, Allo, YouTube TV, Google Earth, and YouTube Studio Beta all block Windows 10’s default browser, Microsoft Edge, from accessing them and they all point users to download Chrome instead. Google Meet, Google Earth, and YouTube TV are also not supported on Firefox with messages to download Chrome.

I wouldn’t call it an epidemic but it’s not a good trend. Best I can tell, it’s server-side UA sniffing that entirely blocks the sites:


If anything, I’d think you’d just let people use the site and display a warning if you’re really worried some particular feature might not work. Or even better, fix it. I have no behind-the-scenes knowledge of why they made the choice to block certain browsers, but it’s hard to imagine a technical limitation that would force it. And if it is, I’d suggest letting it be very publicly known to incentivize the other browsers to support what is needed, assuming it’s an established standard.

Even more concerning than browser-specific websites is seeing browsers ship non-standardized features just because they want them, not behind any vendor prefix or flag. There was a time when web developers would have got out the pitchforks if a browser was doing this, but I sense some complacency seeping in.

These days, the vibe is more centered around complaining about other browsers lack of support for things. For example, one browser ships something, we see one green dot in caniuse, and we lambast the other browsers to catch up. Instead, we might ask, was it a good idea to ship that feature yet?

No modern browser is shipping vendor prefixes anymore since we all ultimately decided that was a bad idea. A side effect of that is that shipping a new feature in CSS or JavaScript is all the riskier. I would think shipping an unprefixed feature to a stable version of the browser would mean the feature is standardized and not going to significantly change. Yet, it’s been happening.

In CSS, Chrome shipped motion-* properties, but then that all changed to offset-*, and the old motion-* properties just stopped working. That’s more than just annoying, that kind of thing helps developers justify saying, “I just build this site for Chrome, if you wanna use it, use Chrome.” Fine for a demo, perhaps, but bad for the web industry as a whole. Again, I have no special insight into why this happens, I’m just a developer looking in from the outside.

Here’s another CSS one I just saw the other day. People are excited about text-decoration-skip: ink; because it looks great and helps people. They are using it a lot. But apparently, that’s not the correct name for it? It’s been changed to text-decoration-skip-ink: auto; and so Chrome 64 is canning text-decoration-skip: ink;. This stuff is hard to keep up with even while actively trying.

Chris Krycho had a take on it recently as well:

Over the past few years, I’ve increasingly seen articles with headlines that run something like, “New Feature Coming To the Web” — followed by content which described how Chrome had implemented an experimental new feature. “You’ll be able to use this soon!” has been the promise.

The reality is a bit more complicated. Sometimes, ideas the Chrome team pioneers make their way out to the rest of the browsers and become tools we can all use. Sometimes… they get shelved because none of the other browsers decide to implement them.

Many times, when this latter tack happens, developers grouse about the other browser makers who are “holding the web back.” But there is a fundamental problem in this way of looking at things: Chrome isn’t the standard. The fact that Chrome proposes something, and even the fact that a bunch of developers like it, does not a standard make. Nor does it impose an obligation to other browsers to prioritize it, or even to ship it.

This isn’t all to throw Chrome under the bus. I’m a Chrome fan. I’m sure there are examples from all the major vendors in the same vein. I’d just like my two cents to be careful now. The web is the best platform to build for and generally heading in a direction that makes that even truer. The easiest way to screw that up is not being careful with standards.

Careful Now is a post from CSS-Tricks