2010864 - Applications action menu dropdown option overflows and causes scroll

Status: VERIFIED FIXED

(Firefox :: Settings UI, defect, P3)

Description

[Mark Kennedy [:mark]]

Attachment: applications-action-menu-overflow.mp4

Steps to reproduce

1. Go to Settings
2. Scroll down to Applications section
3. Click to open last dropdown menu in Actions column

Actual Behavior
Opening dropdown causes it to overflow and the panel to scroll

Expected Behavior
Opening dropdown shouldn't cause a scroll

Comment 1

[Mark Kennedy [:mark]]

The dropdown is a <panel-list> and looks like we have Bug 1866864 to try using the Popover API to resolve.

Comment 2

[Tim Giles [:tgiles]]

Attachment: Bug 2010864 - Add support for popover in panel-list. r=#recomp-reviewers

add Anna's popover patch

Ensure panel-list popovers are anchored to invoker

Make popover panel-lists open in the correct direction

Comment 3

[Tim Giles [:tgiles]]

Attachment: Bug 2010864 - Remove duplicate event handler in about:logging. r=#recomp-reviewers

Remove redundant parts of aboutLogging

Trying to figure out why the popover immediately closes when
you click and let go of the mouse button.

Comment 4

[Tim Giles [:tgiles]]

Attachment: Bug 2010864 - Add support for popover in panel-list. r=#recomp-reviewers

These changes address the issue with the new Applications setting group
where opening the dropdown would cause the group to increase in height
due to the dropdown menu elements. Users would need to scroll down
further to see the options in this menu, and then the group would shrink
in height after selecting an option from the menu.

To solve this issue, we use the popover API on the panel-list custom
element. The popover API makes the panel-list behave like the menupopup
custom element, which is the behavior we want. Now opening a select menu
in the Applications section causes the associated panel-list to appear
on top of the group, but anchored to the element that opened it.

However, to ensure that the panel-list appears anchored to the opening
element, we need to override some of the default UA styles for
[popover]. By default, a popover appears centered on the window, so we
override the margin to ensure the panel-list appears anchored to the
correct element.

Comment 5

[Tim Giles [:tgiles]]

Attachment: Bug 2010864 - Remove duplicate event handler in about:logging. r=#recomp-reviewers

Since the MenuController from moz-button handles the panel-list state
logic, we don't need this duplicate handler in about:logging.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/3f109fa80885
https://hg.mozilla.org/integration/autoland/rev/ce1c20d0c677
Add support for popover in panel-list. r=desktop-theme-reviewers,mkennedy,emilio
https://github.com/mozilla-firefox/firefox/commit/518d3cc5e8b7
https://hg.mozilla.org/integration/autoland/rev/8822fb29e233
Remove duplicate event handler in about:logging. r=mkennedy

Comment 7

[amarc]

https://hg.mozilla.org/mozilla-central/rev/ce1c20d0c677
https://hg.mozilla.org/mozilla-central/rev/8822fb29e233

Comment 8

[BMO Github Automation]

Authored by https://github.com/TGiles
https://github.com/mozilla/enterprise-firefox/commit/3f109fa808858020956de3474f9350569e3f42b6
[enterprise-main] Bug 2010864 - Add support for popover in panel-list. r=desktop-theme-reviewers,mkennedy,emilio

Authored by https://github.com/TGiles
https://github.com/mozilla/enterprise-firefox/commit/518d3cc5e8b7c3baa626c1b34d3629d98c353bbf
[enterprise-main] Bug 2010864 - Remove duplicate event handler in about:logging. r=mkennedy

Comment 9

[Mark Striemer [:mstriemer]]

Attachment: Revert "Bug 2010864 - Add support for popover in panel-list. "

This reverts commit 3f109fa808858020956de3474f9350569e3f42b6.

Comment 10

[Pulsebot]

https://github.com/mozilla-firefox/firefox/commit/07ddf216d841
https://hg.mozilla.org/releases/mozilla-beta/rev/9ba2e11aece1

Comment 11

[Ardelean Oana, Desktop Test Engineering [:oardelean]]

Verified as fixed on Firefox Nightly 150.0a1 and Firefox 149.0b2 on Windows 10, Ubuntu 22, macOS 13.

Opening the dropdown does not cause scrolling.

Please note that the issue could not be reproduced, as builds prior to 2026-02-13 do not contain the new Settings UI design, and the issue is no longer reproducible on 2026-02-13 Firefox Nightly builds.