2072965 - Sidebar header text for extensions is not shown when `Open tools from sidebar` is unchecked

Status: RESOLVED FIXED

(Firefox :: Sidebar, defect, P1)

Description

[Fanolian]

Attachment: Firefox sidebar with extensions.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:158.0) Gecko/20100101 Firefox/158.0
Build ID: 20260916202159

Extension name is not shown in the sidebar header when Open tools from sidebar, introduced in bug 2047653, is unchecked.

Steps to reproduce

1. In a new profile, install an extension that utilise sidebar, e.g.
   https://addons.mozilla.org/en-GB/firefox/addon/tree-style-tab/
   https://addons.mozilla.org/en-GB/firefox/addon/contextsearch-web-ext/
   https://addons.mozilla.org/en-GB/firefox/addon/firemonkey/
2. Enable sidebar.
3. Uncheck Open tools from sidebar. (Or set sidebar.visibility to hide-launcher in about:config.)
4. Click the sidebar header and select an installed extension.
5. Observe the header text.

Actual result

The extension name is not shown. It is available in the panel switcher (dropdown menu) though.
Please refer to the attached screenshot.

Expected result

The header shows the name of extension.

Comment 1

[Hackbot]

In hide-launcher mode sidebar-panel-header.css hides .sidebar-panel-title, so the visible header text is no longer the heading but sidebar-panel-switcher's own label, which sidebar-panel-switcher.mjs derives by matching its view against SidebarController.getRevampSwitcherItems(). Extension panels instantiate the header from webext-panels.xhtml with no view attribute and webext-panels.js sets only heading, so the lookup matches nothing and the label falls back to ""; the same mismatch also leaves the current extension unchecked in the dropdown.

Fix: Have the switcher fall back to SidebarController.currentID when its view is empty, rather than plumbing view in from webext-panels.js, because sidebar-panel-header.css deliberately keys extension-panel padding on the absence of view (bug 2062881). Then extend browser_hide_sidebar.js, whose switcher-label coverage is built-in panels only, with an extension panel case.

Suggested severity: S3. Every extension panel header renders empty in this mode, but nothing is functionally blocked and the panel name is still visible in the switcher dropdown, and reaching it requires unchecking the non-default Open tools from sidebar setting with horizontal tabs.

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Comment 2

[Kelly Cochrane [:kcochrane]]

Attachment: Bug 2072965 - Ensure sidebar extension panel header is shown when 'Open tools from sidebar' is unchecked

Comment 3

[Kelly Cochrane [:kcochrane]]

This is occurring on all platforms

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/88b81b9e07b7
https://hg.mozilla.org/integration/autoland/rev/c68d29eb2646
Ensure sidebar extension panel header is shown when 'Open tools from sidebar' is unchecked r=sidebar-reviewers,sfoster

Comment 5

[Silaghi Andreea]

https://hg.mozilla.org/mozilla-central/rev/c68d29eb2646

Comment 6

[BugBot [:suhaib / :marco]]

The patch landed in nightly and beta is affected.

:kcochrane, please make an uplift decision for beta:

• Nominate the patch for beta uplift approval if the fix should be included in this release, or
• Set status-firefox157 to wontfix if the fix can wait for the next release.

See Requesting an Uplift for documentation on how to request an uplift.

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