Do you happen to be on Chromium or Opera? On Linux Mint here, I can’t reproduce the “big blocking plus icon” in Firefox - it only shows up for me in Chromium-based browsers.
A few quick things that did change the symptom on my end:
- Toggle hardware acceleration (on/off) in Chromium/Opera, then restart.
- Try launching once with
--disable-gputo see if it’s the GPU path. - Check
chrome://gpufor any compositing/accelerated canvas issues. - If you’re on Wayland (say you’re using Edge on Linux), test
--ozone-platform=waylandvsx11(or vice-versa). - Reset any zoom/scaling quirks (browser zoom 100%, OS fractional scaling off).
- Try with all extensions disabled (Incognito with no extensions is a quick check).
it helps to share:
- your Distro/DE (e.g. Mint Cinnamon), kernel, and windowing system (X11/Wayland)
- Browser + version (
chrome://version), and whether hardware acceleration is on - GPU + driver (mesa/NVIDIA proprietary)
- Repro steps and a short screen capture
FWIW I’ve sent reports to Google/Opera already; Firefox on Mint renders the composer normally for me, so this looks confined to the Chromium path.