I've tested an upgrade of Ubuntu MATE (running Lunar) with -proposed enabled with version 1:23.04.7 installed and the fonts in the body of the ubuntu-release-upgrader were legible, however the title bar was corrupted but that's fine.
I've tested an upgrade of Ubuntu MATE (running Lunar) with -proposed enabled with version 1:23.04.7 installed and the fonts in the body of the ubuntu- release- upgrader were legible, however the title bar was corrupted but that's fine.