[Webkit-unassigned] [Bug 205942] New: The visibilitychange event does not fire on iOS when entering the tab switcher

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=205942

            Bug ID: 205942
           Summary: The visibilitychange event does not fire on iOS when
                    entering the tab switcher
           Product: WebKit
           Version: Safari 13
          Hardware: Unspecified
                OS: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: DOM
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: philip at philipwalton.com

** Current behavior: **

When opening the tab switcher in Safari on iOS, the `visibilitychange` event will only fire once a user switches to a new tab. If the user instead closes the tab, then no `visibilitychange` event is fired (neither is `pagehide`, `beforeunload`, or `unload` FWIW, though I don't think those events should offer the same guarantees as `visibilitychange`).

STR:

1. Visit https://visibilitychange-logger.glitch.me on an iPhone
2. Click the tab switcher button in the bottom right
3. Close the tab
4. Re-visit https://visibilitychange-logger.glitch.me and notice that no events were logged

(note: `visibilitychange` events *are* logged if you actually switch to another tab)

** Proposed behavior: **

In my opinion, the `visibilitychange` event should fire as soon as the tab switcher button is pressed. That would guarantee that at least the hidden state is triggered regardless of whether the user switches tabs or closes the tab. (This is also consistent with how the `visibilitychange` event fires on Chrome on both Android and iOS)

Alternatively, if https://bugs.webkit.org/show_bug.cgi?id=151234 can be fixed to ensure the `visibilitychange` event fires any time the page goes away (including closing it from the tab switcher), that would also solve this problem.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20200108/75b6b732/attachment.htm>