incompatible host fonts cache causing snap app instability
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
snapd |
In Progress
|
Undecided
|
James Henstridge |
Bug Description
Originally reported and investigated in the snapcraft forum here: https:/
The problem appears to be caused by making the fonts cache from the host accessible inside the snap mount namespace. The reason we are doing this is to avoid rebuilding the cache on the first run of an application. However, this only works then the binary fonts cache generated on the host is compatible with the fontconfig inside the snap.
As we later discovered, despite advertising a compatible (cache-7) format, the newer version of fontconfig available in Arch and Fedora 32, generate cache files that are not properly handled by fontconfig from gnome-3-28-1804 snap (or basically 20.04 and earlier).
When the incompatible cache is present, we have seen the fonts being rendered as boxes (fontconfig could not identify glyphs?), or plain segfaults with backtrace going to font related code (eg. zoom-client, glimpse-editor).
Deeper investigation led to identifying a commit that introduced breakage: https:/
Changed in snapd: | |
assignee: | nobody → James Henstridge (jamesh) |
status: | Confirmed → In Progress |
incompatible host fonts cache causing snap app instability
https:/ /github. com/postmanlabs /postman- app-support/ issues/ 10449