Am 12.11.20 um 09:35 schrieb to...@tuxteam.de:
On Wed, Nov 11, 2020 at 11:57:08PM +0100, mmdebmail2...@marwedels.de wrote:
I don't know (not sure I'd want to) where Gtk keeps its MIME types
database these days. But, as a shot in the dark: have you checked
that your /etc/mime.types is sane? What does 'grep png /etc/mime.types'
say?
The file comes with Debian package mime-support, in case you need
a new one.
I fixed the error.
After figuring out, that glib2.0 had no data to compare the png data to
in cache_get_mime_type_for_data, I stepped through
xdg_mime_init_from_directory and discovered only a few data for
mimetypes were added from my ~/.local/share directory. Stepping through
the same code on a different computer, most data came from
/usr/share/mime/mime.cache, but the file was missing on my computer.
Running update-mime-database /usr/share/mime/ as root solved the
problem. Took me ~7 hours to figure this out ;) Maybe this was the
result of an upgrade. Because this was when the error occurred the first
time.