1954364 - Error when dragging tab group between windows: "can't access property 'inRDMPane', this.browsingContext is null"

Status: RESOLVED DUPLICATE of bug 1953724

(Firefox :: Tabbed Browser, defect)

Description

[tabmix.onemen]

When dragging a tab group from one window to another, the following error occurs:

17:06:28.649 Uncaught (in promise) TypeError: can't access property "inRDMPane", this.browsingContext is null
    get fullZoom chrome://global/content/elements/browser-custom-element.js:712
    get fullZoom chrome://browser/content/tabbrowser/tabbrowser.js:689
    ZoomManager_getZoomForBrowser chrome://global/content/viewZoomOverlay.js:35
    get zoom chrome://global/content/viewZoomOverlay.js:19
    FullZoom_updateCommands chrome://browser/content/tabbrowser/browser-fullZoom.js:341
    updateZoomUI resource:///modules/ZoomUI.sys.mjs:193
browser-custom-element.js:712:11

Steps to reproduce:

• Start Firefox Nightly
• Open a second window with one tab
• Add the tab to a group
• Drag the group-label from the second window to the first window

The error only occurs when all tabs in the 2nd window are contained within the group being dragged (no other tabs exist in that window).
Observed on Windows 11

Comment 1

[Dão Gottwald [:dao]]

I can't seem to reproduce this in Nightly. Are you still seeing this?

Comment 3

[tabmix.onemen]

(In reply to Dão Gottwald [:dao] from comment #1)

I can't seem to reproduce this in Nightly. Are you still seeing this?

No, I can't reproduce it