zoom cannot see whole screen after boot with external monitor connected then monitor disconnected

Distribution

Mint 22

Package version

6.2.9

Graphics hardware in use

AMD Ryzen 7 PRO 7840U w/ Radeon 780M Graphics

Frequency

Always

Bug description

When using the zoom screen accessibility function, it is not possible to explore the entire screen under certain conditions. When zoomed in, moving the mouse to the far right does not show the furthest right side of the screen, for example. Related, zooming shows the zoom in a subsection of the desktop, not the entire desktop.

Steps to reproduce

Scenario:

Thinkpad T42s AMD Ryzen 7 PRO 7840U w/ Radeon 780M Graphics laptop plugged into external monitor via USB-C connection. Laptop panel has 1920x1200 resolution. External display has 2560x1440 resolution.

1. Boot laptop computer with external display connected.
2. Activate zoom. Zoom works but in a subsection of the external display
3. Unplug USB-C cable.
4. Activate zoom - zoom does not allow you to move around the entire screen

The display setup

The zoomed window - note how only part of the display shows the zoom. That is the 'side' issue. The main issue is when the opposite happens, i.e. the zoom only allows access to part of the display.

Expected behavior

Should be able to mouse around the zoom to see whole display.

Additional information

No response

No source files, tests, or entry points are named. Start by reproducing the zoom behavior with the stated external-monitor connect/disconnect sequence on Cinnamon, then trace the zoom and display-configuration handling. Done means zoom can reach the entire remaining display after the monitor is disconnected, with regression coverage if an appropriate test location is found.