(Ubuntu Cinnamon) Mouse pointer mostly loses theming once Ubiquity is started

[Aaron Rainbolt]

Steps to reproduce:

1. Boot the latest Ubuntu Cinnamon Lunar Beta ISO.
2. Click "Try Ubuntu Cinnamon".
3. Note that the mouse pointer is themed properly (you can open a terminal window and attempt to resize it to confirm this).
4. Double-click "Install Ubuntu Cinnamon 23.04".

Expected result: The mouse pointer should continue to be themed properly.

Actual result: The mouse pointer loses theming and looks like the mouse pointer that the X server usually displays by default.

Additional info: When hovering over certain parts of other apps, the mouse pointer theme seems to return, and then the theming vanishes again when the mouse pointer moves outside those areas. It's kind of hard to describe, but try opening LibreOffice after opening Ubiquity and move the mouse around, you'll see what I mean.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
https://iso.qa.ubuntu.com/qatracker/reports/bugs/2013381

[Aaron Rainbolt (arraybolt3)]

This is also happening in the installation environment (when you first boot and then click "Install Ubuntu Cinnamon" rather than "Try Ubuntu Cinnamon"). But there the mouse pointer is always the default X pointer all the time.