A rather geeky/technical weblog, est. 2001, by Bramus
border-radius with a View Transition, revisited
Instead of duplicating an animation on the ::view-transition-group pseudo, you can also rely on CSS transitions on the original element … if you’ve set it up correctly.
In April I attended #BlinkOn, the conference for web platform contributors in the Chromium open source project. At the conference I gave a presentation about “CSS Parser Extensions”, a wild idea I have to fix CSS polyfilling once and for all.
If you didn’t know, polyfilling CSS features is extremely hard, mainly because the CSS Parser discards what it does not understand. So what if, instead of having authors write their own parser and cascade to polyfill a CSS feature, they could teach the parser some new tricks?
After a wonderful week in San Francisco and Mountain View, the week ended in a disaster when my colleague and friend Adam was told to find another role at Google – Roughly translated: they fired him without actually firing him.
border-radius with a View Transition To smoothly animate things like borders as part of a View Transition, you need to duplicate that animation onto the ::view-transition-group. For best effect, have the View Transition separately capture the background and foreground of the element you’re animating.
New in Chrome 134 on Android: the ability to place the Address Bar (aka “Omnibox”) at the bottom. To enable it, go to Chrome’s Settings, locate and tap “Address Bar”, and choose “Bottom”.
Beware when manipulating the coordinates of the View Transition’s ::view-transition-group(*) pseudo. Depending on where you read those coordinates from, you might end up with layout jumps when writing them back. This post details the pitfalls and how to deal with them, unlocking more performant animations on the ::view-transition-group() pseudo along the way.
StyleObserver: Element.matchContainer()
Martin Winkler published a package that polyfills Element.matchContainer to get notified in script when a Container Query matches/unmatches. Under the hood, it uses a StyleObserver.
@function + CSS if() = 🤯
Support for Nested Container Queries and the CSS if() function inside CSS Custom Functions make @function very powerful.
::view-transition-group(*) animations
If the dimensions of the ::view-transition-group(*) don’t change between the old and new snapshot you can optimize its keyframes so that it animates on the compositor.