Gnome shell text getting messed up

image showing messed up ubuntu gnome shell text

im facing this problem since recent upgrade, all texts related to gnome top panel,overlay and gnome shell get messed up, only few letters are displayed. just au[blank spaces for missing letters]s is being displayed for audacious in gnome search results. Whatever i type in the search bar get messy too.

i dont face this everytime i use ubuntu. the last time i faced the problem i ran software update and the problem got solved. It worked fine for a few days but i got the problem back.

text in applications are fine.

I'm suffering the same issue and I'm debugging it. While I haven't found the root cause, I've found that the issue is in cogl's glyph cache for Pango. You can use a debugger to clear this cache. I'm going to detail the steps here, but I should warn you that this is a bit of an expert option.

Preparation you need to do once to make the workaround work:

sudo apt-get install gdb gnome-shell-dbg libclutter-1.0-dbg libcogl-pango20-dbg

Then whenever you run into the issue, clear the font cache by running the following command line:

sudo gdb -p `pgrep -u $USER -x gnome-shell` <<<"print /r _cogl_pango_renderer_clear_glyph_cache((CoglPangoRenderer*)(_cogl_pango_font_map_get_priv(clutter_context_get_pango_fontmap())->renderer))"

This works splendidly for me, but I should warn you that if this command goes awry for any reason, it may hang your system. If that happens, a reboot is the only thing that fixes it.

I'm going to investigate further what, exactly, is wrong with the glyph cache, and open a bug report upstream.

Hope that helps!

Explanation of the command line: the part between backticks finds the process id for gnome-shell. That is used to attach the debugger gdb to the process; you need to be root (sudo) to do that. The part between <<<" and " is the function call for clearing the glyph cache.