301070 2025-10-19 20:03:50 -0700 [css-anchor-position-1] Anchor positioned popover temporarily misplaced during transition 2026-04-02 15:51:23 -0700 1 1 1 Unclassified WebKit Layout and Rendering Safari 26 Unspecified Unspecified RESOLVED DUPLICATE 301510 InRadar P2 Major --- 301461 1 mic.gallego kiet.ho ap bfulgham fantasai.bugs graouts kiet.ho simon.fraser tien.nguyenkhac webkit-bug-importer zalan oldest_to_newest 2152485 0 mic.gallego 2025-10-19 20:03:50 -0700 Hello, On Safari 26, using a display discrete transition crashes the browser when used with anchor positioning. The issue can be reproduced here: https://codepen.io/bakura10/pen/GgoyVEB Just click on One then Two to reproduce the issue. No issue on Chrome. 2152715 1 ap 2025-10-20 14:43:05 -0700 Thank you for the report! I cannot reproduce this with Safari Technology Preview, but I also cannot reproduce this with an older build that I have around. Could you please attach a crash log, so that we could verify whether this is a known issue? 2152728 2 zalan 2025-10-20 15:03:43 -0700 I can make the browser hang on older build (e.g. 298280@main) but I am not seeing it on newer builds. 2152824 3 mic.gallego 2025-10-20 18:01:58 -0700 Hello, On Safari 26 stable, the browser crashes. On TP, the browser does not crashes but the feature is not working correctly :). 2152973 4 ap 2025-10-21 08:20:49 -0700 Thank you for the clarification. It's not clear to me personally what "is not working correctly" means exactly, but perhaps layout experts CC'ed on the bug do understand. 2152980 5 mic.gallego 2025-10-21 08:36:39 -0700 Hello @Alexey, Sorry, I just realized the Gist was incomplete on the TP. Please click on "Two" and click outside. You will see that the popover is repositioned incorrectly before being closed. On Chrome, the popover stays properly positioned during the whole animation. 2152987 6 ap 2025-10-21 08:46:04 -0700 Ah! Now I can reproduce. Re-titling to track the issue that we still need to fix. 2152989 7 webkit-bug-importer 2025-10-21 08:47:36 -0700 <rdar://problem/163119386> 2153095 8 kiet.ho 2025-10-21 13:03:22 -0700 Might be dupe of https://bugs.webkit.org/show_bug.cgi?id=301057 2153164 9 kiet.ho 2025-10-21 16:40:45 -0700 I can't reproduce the crash, but the issue of anchor positioned popover at the wrong location when dismissing is a known issue that I'm working on. Part 1 of the fix is here: https://bugs.webkit.org/show_bug.cgi?id=301056 2154234 10 graouts 2025-10-25 05:44:34 -0700 This seems specific to using an accelerated property, I filed bug 301461. 2157730 11 tien.nguyenkhac 2025-11-10 12:33:22 -0800 This crash instantly for me on Safari 26. 2196397 12 kiet.ho 2026-04-02 15:15:13 -0700 This demo seems to work fine on Safari 26.4: https://codepen.io/bakura10/pen/GgoyVEB 2196408 13 kiet.ho 2026-04-02 15:51:23 -0700 This was fixed in bug 301510. *** This bug has been marked as a duplicate of bug 301510 ***