1697725 - Warn on close window grays out page content behind sheet

Status: RESOLVED INVALID

(Firefox :: General, defect)

Description

[Asif Youssuff]

Attachment: Screen Shot 2021-03-11 at 2.03.21 AM.png

Noticed that the modal dialog that appears when closing a window with tabs in it grays out the page content behind the dialog, rendering it inconsistent with platform behavior of sheets (the closest analog to this dialog).

Steps to reproduce:

1. Ensure browser.tabs.warnOnClose is set to true
2. Open several tabs
3. Click close window button in window (not tab)

What happens:

Modal dialog appears asking whether I want to close the window. The window content is grayed out.

Expected result:

Like release Firefox and other modal dialogs presented in sheets (like in macOS). The window content should not be grayed out.

102:12.42 INFO: Narrowed inbound regression window from [9cf59af5, 2a990b27] (3 builds) to [9cf59af5, 1129347e] (2 builds) (~1 steps left)
102:12.42 INFO: No more inbound revisions, bisection finished.
102:12.42 INFO: Last good revision: 9cf59af57183940e3d5f629f4ea29b499e956fca
102:12.42 INFO: First bad revision: 1129347e2aadcde6d60e03b6917539413c306639
102:12.42 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=9cf59af57183940e3d5f629f4ea29b499e956fca&tochange=1129347e2aadcde6d60e03b6917539413c306639

Comment 1

[Asif Youssuff]

Attachment: textedit sheet

Example sheet in TextEdit screenshot attached.

Comment 2

[Sören Hentzschel]

Attachment: screenshot

Screenshot from Firefox 86, no Proton, old dialog, on a current version of macOS (11.2.3). The window content is greyed out. The same is true for TextEdit.

Maybe Apple changed the behaviour of modal dialogs in macOS 11 but since Firefox behaves like the current version of macOS I would argue that the current Firefox behaviour is the correct one (and that it's totally fine to do this on all versions of macOS).

Comment 3

[Asif Youssuff]

Apple documentation isn't even helping here, unfortunately, as their latest HIG doesn't show any Big Sur styling: https://developer.apple.com/design/human-interface-guidelines/macos/windows-and-views/sheets/

Sören, are sheets also not a UI element in macOS anymore? Your screenshot shows the dialog centered instead of expanding from the window frame (per documentation).

While I have not upgraded to the new macOS for various reasons (including the odd UI choices), pre-macOS 11 versions remain in active support (with the last update only a month ago) both by Apple and Mozilla. Mozilla has supported different themes for various Windows versions, even those out of support by Microsoft.

I'll also note that both Google and Microsoft's browsers do the expected behavior here in their sheet-alike UIs (eg the Print dialogs), even when they theme other widgets differently (like buttons).

Comment 4

[:Gijs (he/him)]

We already grey out content for in-page dialogs (alert/prompt/confirm & beforeunload warnings) and for other tab-specific dialogs (http auth warning, insecure form submission warning, print dialog), too, also pre-proton, and in the case of the web content dialogs we have done this for 10 years or so. It gives the user clear feedback that interaction with the greyed out area is not possible. We do this on all OSes. This isn't a bug.