Various hit-testing/scrolling tests are suddenly producing intermittent failures since July 30 #21339
Description
09:09 <jdm> I am really worried about how all of our automated tests related to hit testing and scrolling are suddenly having intermittent failures in the past couple days
09:10 <jdm> it started 4 days ago; there's been #21283, #21295, #21312, #21321, and now nox has hit three more in a single PR today
09:10 <crowbot> Issue #21312: Intermittent failure in /_mozilla/mozilla/hit_test_multiple_sc.html - https://github.com/servo/servo/issues/21312
09:10 <crowbot> Issue #21295: Intermittent failure in /css/cssom-view/elementFromPosition.html - https://github.com/servo/servo/issues/21295
09:10 <crowbot> Issue #21321: Intermittent failure in /_mozilla/mozilla/scrollBy.html - https://github.com/servo/servo/issues/21321
09:10 <crowbot> Issue #21283: Intermittent failure in /_mozilla/mozilla/hit_test_pos_fixed.html - https://github.com/servo/servo/issues/21283
#21312, #21295, #21321, #21283, #21338 are the ones that fit this pattern so far.