255837 2023-04-22 22:06:11 -0700 The `beforeunload` event doesn't occur when clicking on a link 2023-12-01 11:11:28 -0800 1 1 1 Unclassified WebKit Page Loading Safari 16 All All NEW https://bugs.webkit.org/show_bug.cgi?id=206366 BrowserCompat, InRadar P2 Blocker --- 1 chewteeming01 webkit-unassigned ap beidson cdumez karlcow nham rniwa webkit-bug-importer oldest_to_newest 1950616 0 466050 chewteeming01 2023-04-22 22:06:11 -0700 Created attachment 466050 The HTML file contains a link that should be intercepted by the beforeunload event. Summary: Calling `event.preventDefault()` when listening to a `beforeunload` event on the `window` should rightly prompt the user if they want to stay or leave the page. This is currently broken in macOS Safari 16.4. OS: I have tested this issue on both iOS Safari 16.4.1 and macOS Safari Version 16.4 (18615.1.26.11.23). Steps to reproduce: An example page such as https://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_onbeforeunload will not work on iOS, but will still work on macOS (it only works on macOS because the unload event is contained in an iframe.) I have attached a sample HTML file that can be opened in a Webkit browser. Clicking on the link should prompt the user with an alert. The code was copied from the example provided by W3Schools. Actual results: The browser navigates to the link normally. Expected results: The browser prompts the user with an alert to stay or leave the page before navigating to the new page. Build Date & Hardware: Apple M1 Pro macOS 13.3.1 (22E261) Additional information: I first noticed this issue during some cross-browser tests for cancelling the `beforeunload` event. Only Safari was failing the tests at the time so I started to investigate. The PR with those cross-browser tests can be found here: https://github.com/sveltejs/kit/pull/9747 1950662 1 ap 2023-04-23 14:15:41 -0700 The attached test case doesn't contain "preventDefault()", is this one that you intended to provide? It does behave differently that in Chrome, but I'd like to make certain that we are talking about the same issue. 1950674 2 466055 chewteeming01 2023-04-23 17:19:59 -0700 Created attachment 466055 The HTML file contains a link that should be intercepted by the beforeunload event (event.preventDefault). 1950675 3 chewteeming01 2023-04-23 17:21:29 -0700 (In reply to Alexey Proskuryakov from comment #1) > The attached test case doesn't contain "preventDefault()", is this one that > you intended to provide? It does behave differently that in Chrome, but I'd > like to make certain that we are talking about the same issue. Sorry about that. I forgot to include the `event.preventDefault()` line in the test case. I've uploaded an updated test case that includes the line. 1952064 4 webkit-bug-importer 2023-04-29 22:07:19 -0700 <rdar://problem/108706692> 1996287 5 chewteeming01 2023-12-01 11:11:28 -0800 After another look at this, it seems the confirmation dialog isn't appearing because the `beforeunload` event is never invoked when clicking on the link. 466050 2023-04-22 22:06:11 -0700 2023-04-22 22:06:11 -0700 The HTML file contains a link that should be intercepted by the beforeunload event. test.html text/html 431 chewteeming01 PCFET0NUWVBFIGh0bWw+CjxodG1sPgo8Ym9keSBvbmJlZm9yZXVubG9hZD0icmV0dXJuIG15RnVu Y3Rpb24oZXZlbnQpIj4KPGgxPkhUTUwgRE9NIEV2ZW50czwvaDE+CjxoMj5UaGUgYmVmb3JldW5s b2FkIEV2ZW50PC9oMj4KCjxwPlJlbG9hZCB0aGlzIHBhZ2UsIG9yIGNsaWNrIG9uIHRoZSBsaW5r IGJlbG93IHRvIGludm9rZSB0aGUgb25iZWZvcmV1bmxvYWQgZXZlbnQuPC9wPgoKPGEgaHJlZj0i aHR0cHM6Ly93d3cudzNzY2hvb2xzLmNvbSI+Q2xpY2sgaGVyZSB0byBnbyB0byB3M3NjaG9vbHMu Y29tPC9hPgogICAgCjxzY3JpcHQ+CmZ1bmN0aW9uIG15RnVuY3Rpb24oZXZlbnQpIHsKICBjb25z b2xlLmxvZyhldmVudCk7CiAgcmV0dXJuICJXcml0ZSBzb21ldGhpbmcgY2xldmVyIGhlcmUuLi4i Owp9Cjwvc2NyaXB0PgoKPC9ib2R5Pgo8L2h0bWw+Cgo= 466055 2023-04-23 17:19:59 -0700 2023-04-23 17:19:59 -0700 The HTML file contains a link that should be intercepted by the beforeunload event (event.preventDefault). test.html text/html 457 chewteeming01 PCFET0NUWVBFIGh0bWw+CjxodG1sPgo8Ym9keSBvbmJlZm9yZXVubG9hZD0icmV0dXJuIG15RnVu Y3Rpb24oZXZlbnQpIj4KPGgxPkhUTUwgRE9NIEV2ZW50czwvaDE+CjxoMj5UaGUgYmVmb3JldW5s b2FkIEV2ZW50PC9oMj4KCjxwPlJlbG9hZCB0aGlzIHBhZ2UsIG9yIGNsaWNrIG9uIHRoZSBsaW5r IGJlbG93IHRvIGludm9rZSB0aGUgb25iZWZvcmV1bmxvYWQgZXZlbnQuPC9wPgoKPGEgaHJlZj0i aHR0cHM6Ly93d3cudzNzY2hvb2xzLmNvbSI+Q2xpY2sgaGVyZSB0byBnbyB0byB3M3NjaG9vbHMu Y29tPC9hPgogICAgCjxzY3JpcHQ+CmZ1bmN0aW9uIG15RnVuY3Rpb24oZXZlbnQpIHsKICBjb25z b2xlLmxvZyhldmVudCk7CiAgZXZlbnQucHJldmVudERlZmF1bHQoKTsKICByZXR1cm4gIldyaXRl IHNvbWV0aGluZyBjbGV2ZXIgaGVyZS4uLiI7Cn0KPC9zY3JpcHQ+Cgo8L2JvZHk+CjwvaHRtbD4K Cg==