LGTM1 On Thu, Apr 6, 2023 at 2:01 AM Chris Harrelson <chris...@chromium.org> wrote:
> Contact emailschris...@chromium.org > > Specificationhttps://drafts.csswg.org/css-overflow-3/#valdef-overflow-auto > > Summary > > Removes the overflow:overlay scrolling mode, and makes overlay a legacy > alias of auto. overflow:overlay is the same as overflow:auto, except that > it does not prevent content from extending into the scrollbar gutter, in > cases where non-overlay OS scrollbars are present. (If overlay scrollbars > are present, there is no effect.) Example: With overflow:overlay: > https://output.jsbin.com/yujenuq/quiet With overflow:auto: > https://output.jsbin.com/ruzogaf/quiet > > > Blink componentBlink>Scroll > <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EScroll> > > TAG reviewNone > > TAG review statusNot applicable > > Risks > > > Interoperability and Compatibility > > Developers currently relying on content overlapping the scrollbar gutter > would instead see some additional line wrapping. Users, on the other hand, > would be able to see more content that is currently invisible underneath a > scrollbar. On platform configurations with overlay scrollbars in the OS, > this change has no effect; it only applies to situations where a > non-overlay scrollbar is configured by the browser. Use counter: > https://chromestatus.com/metrics/feature/timeline/popularity/2995 > Adoption is more than 2% of page loads. However: * I don't think any sites > will break for users. * Some sites will improve because they are currently > preventing users from seeing some content that is accidentally underneath a > non-overlay scrollbar. * Interop will be achieved with Webkit and Gecko. I > reviewed > <https://docs.google.com/document/d/1KA-eavI44Vc6WTDDlAKvUfv7x2BThTeEY9-bw69Jj2Q/edit#> > 20 sites listed from the HTTPArchive and found nothing broken. The only > "downside" was that the visible spacing between content and the scrollbar > increased by a few pixels in some cases. In none of these cases was it a > significant change to the user experience. On two of the sites, > -webkit-scrollbar was also used to make the scrollbar narrower when not > hovered, in conjunction with overflow:overlay to reduce the gutter spacing. > On those sites, the gutter got a bit wider but the user experience was not > materially affected. > > > *Gecko*: Shipped/Shipping ( > https://github.com/mozilla/standards-positions/issues/768) > > *WebKit*: Shipped/Shipping ( > https://github.com/WebKit/standards-positions/issues/157) > > *Web developers*: No signals > > *Other signals*: > > Ergonomics > > After this change, sites will no longer be able to avoid reserving space > for the scrollbar. However, this is good, because the scrollbar does take > up space and it's bad for users not to be able to read content obscured by > it. The CSSWG has in the past considered all of this and resolved not to > let developers prevent a scrollbar gutter, because overlay scrollbars are > an OS feature, and it's more important for users to see content than for > developers to micro-manage an important user affordance. See > https://github.com/w3c/csswg-drafts/issues/4501 for example. I found > three use cases developers seemed to want to achieve on these sites: * > Reduce scrollbar gutter size * "force" overlay scrollbars (there is no way > to do that, but overflow:overlay might lead them to that conclusion) * > Reduce the gutter when used in conjunction with a custom scrollbar via > -webkit-scrollbar that reduces its width when not hovered. Use case 3 is > better solved by shipping scrollbar-width in the future ( > https://developer.mozilla.org/en-US/docs/Web/CSS/scrollbar-width) > > > Activation > > None > > > Security > > None > > > WebView application risks > > Does this intent deprecate or change behavior of existing APIs, such that > it has potentially high risk for Android WebView-based applications? > > None > > > Debuggability > > Sites might not know why their line wrapping changed to exclude the > scrollbar gutter. However, this is the existing behavior in Firefox and > Safari, so they would get interop by default. > > > Will this feature be supported on all six Blink platforms (Windows, Mac, > Linux, Chrome OS, Android, and Android WebView)?Yes > > N/A > > > Is this feature fully tested by web-platform-tests > <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> > ?Yes > <https://wpt.fyi/results/css/css-overflow/overflow-overlay.html?label=experimental&label=master&aligned> > > Flag nameOverflowOverlayAliasesAuto > > Requires code in //chrome?False > > Tracking bughttps://bugs.chromium.org/p/chromium/issues/detail?id=554361 > > Sample links > https://output.jsbin.com/yujenuq/quiet > https://output.jsbin.com/ruzogaf/quiet > > Estimated milestones > Shipping on desktop 114 > DevTrial on desktop 114 > Shipping on Android 114 > DevTrial on Android 114 > Shipping on WebView 114 > > Anticipated spec changes > > Open questions about a feature may be a source of future web compat or > interop issues. Please list open issues (e.g. links to known github issues > in the project for the feature specification) whose resolution may > introduce web compat/interop risk (e.g., changing to naming or structure of > the API in a non-backward-compatible way). > None > > Link to entry on the Chrome Platform Status > https://chromestatus.com/feature/5194091479957504 > > Links to previous Intent discussionsIntent to prototype: > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAOMQ%2Bw-F4mOhUMuU3nw423C8CurZKX_wxQvXRPv-XT4Zhsm-XQ%40mail.gmail.com > > This intent message was generated by Chrome Platform Status > <https://chromestatus.com/>. > > -- > You received this message because you are subscribed to the Google Groups > "blink-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to blink-dev+unsubscr...@chromium.org. > To view this discussion on the web visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAOMQ%2Bw9qXWhmS2ap50fGnKZW%2BzeZe2rX8Lcb%2B2967pZXtt0dHw%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAOMQ%2Bw9qXWhmS2ap50fGnKZW%2BzeZe2rX8Lcb%2B2967pZXtt0dHw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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