215664 – [macOS] Web pages are not responding correctly to changes in "Reduce motion" setting

RESOLVED FIXED Bug 215664

[macOS] Web pages are not responding correctly to changes in "Reduce motion" setting

https://bugs.webkit.org/show_bug.cgi?id=215664

Summary [macOS] Web pages are not responding correctly to changes in "Reduce motion" ...

Per Arne Vollan

Reported 2020-08-19 14:47:52 PDT

Web pages are not responding correctly to changes in the "Reduce motion" accessibility setting under System Preferences > Accessibility > Display. This can for example be seen on https://webkit.org/blog-files/prefers-reduced-motion/prm.htm, while changing the setting.

Attachments
Patch (4.89 KB, patch) 2020-08-19 14:59 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (12.90 KB, patch) 2020-08-19 15:51 PDT, Per Arne Vollan	darin: review+	Details Formatted Diff Diff
Patch (14.30 KB, patch) 2020-08-20 07:31 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (14.98 KB, patch) 2020-08-20 08:08 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (15.57 KB, patch) 2020-08-20 08:58 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (15.01 KB, patch) 2020-08-20 09:30 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (16.23 KB, patch) 2020-08-20 12:13 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (16.48 KB, patch) 2020-08-20 12:40 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (17.87 KB, patch) 2020-08-20 15:31 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (17.84 KB, patch) 2020-08-20 16:48 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (17.47 KB, patch) 2020-08-20 17:21 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (16.43 KB, patch) 2020-08-20 17:51 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (14.07 KB, patch) 2020-08-20 18:37 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Patch (14.11 KB, patch) 2020-08-20 19:03 PDT, Per Arne Vollan	no flags	Details Formatted Diff Diff
Show Obsolete (11) View All Add attachment proposed patch, testcase, etc.

Per Arne Vollan

Comment 1 2020-08-19 14:59:21 PDT

Created attachment 406875 [details] Patch

Per Arne Vollan

Comment 2 2020-08-19 15:51:58 PDT

Created attachment 406880 [details] Patch

Per Arne Vollan

Comment 3 2020-08-19 15:52:46 PDT

<rdar://problem/66343795>

Darin Adler

Comment 4 2020-08-19 16:17:26 PDT

Comment on attachment 406880 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=406880&action=review > Source/WebKit/ChangeLog:3 > + [macOS] Web pages are not responding correctly to changes in "Reduce motion" setting How did we happen to overlook this one but not others? Are there any more of these?

Per Arne Vollan

Comment 5 2020-08-19 16:43:28 PDT

(In reply to Darin Adler from comment #4) > Comment on attachment 406880 [details] > Patch > > View in context: > https://bugs.webkit.org/attachment.cgi?id=406880&action=review > > > Source/WebKit/ChangeLog:3 > > + [macOS] Web pages are not responding correctly to changes in "Reduce motion" setting > > How did we happen to overlook this one but not others? Are there any more of > these? Yes, there are potentially more of these cases, since this race is a general issue when updating preferences from the UI process, where the race is usually won by the notification. It might be possible to solve this in a more general way, but I have not been able to think of a way to do that so far. I will try to think of a more general solution. Thanks for reviewing!

Per Arne Vollan

Comment 6 2020-08-20 07:31:42 PDT

Created attachment 406930 [details] Patch

Per Arne Vollan

Comment 7 2020-08-20 08:08:17 PDT

Created attachment 406931 [details] Patch

Per Arne Vollan

Comment 8 2020-08-20 08:58:07 PDT

Created attachment 406935 [details] Patch

Per Arne Vollan

Comment 9 2020-08-20 09:06:40 PDT

The new API test is succeeding locally, but failing on the bots.