Kubuntu 26.10 beta: test Stonking Stingray now

Key points

A follow-up to the Kubuntu 26.10 beta announcement explains how to test "Stonking Stingray" without risking a working machine and how to write a bug report that can be acted on. It also passes on a fix for a Plasma crash that is unrelated to the beta.

Release schedule

• Feature freeze was 20 August and user interface freeze 10 September.
• The mandatory beta was scheduled for 24 September and landed on 1 October.
• Final freeze is 8 October and the final release 15 October.

Testing the beta

• The image is in the beta directory at https://cdimage.ubuntu.com/kubuntu/releases/26.10/beta/; a fresher daily live image is also available.
• Boot it in a virtual machine or on a spare machine, not on the disk used for work, run the installer, use the desktop and note what fails.
• Report one problem per bug, with the exact steps, a Spectacle screenshot when the interface is wrong, and the version string from "About this System". Plasma bugs go to bugs.kde.org; packaging and ISO bugs go to Launchpad, against Ubuntu or Kubuntu.

Crashing Plasma after a Chromium update

• A mid-September Chromium 154 update wrote bad data into the fontconfig cache, and KDE applications including plasmashell crashed on it, sometimes in a loop after a reboot. Google has shipped a fix, so update Chrome or Chromium first.
• If the desktop is still broken, switch to a text login with Ctrl+Alt+F3, run the commands below and reboot. Deleting the folder alone was not enough for several users; rebuilding the cache made the fix stick.

rm -rf ~/.cache/fontconfig
fc-cache -r

Also in the post

• On the beta, Plasma Overview opens with Meta+W and shows every open window as a thumbnail.
• The Discover pick is Tokodon, KDE's Mastodon client.

Summary by DistroNews, based on the original post.