Here is the output of executing "thunar" from bash: ===== Thunar-ERROR **: Failed to load fallback icon from "/usr/share/pixmaps/Thunar/Thunar-fallback-icon.png" (Unrecognized image file format). Check your installation! aborting... Aborted ===== I have viewed this file with feh to confirm that the file both exists and is not corrupted.
This might not be a problem with thunar, but can occur after updating x11-misc/shared-mime-info. After the update, you have to rebuild the mime database in ~/.local directory because the cache format might have changed: update-mime-database ~/.local/share/mime/ Other applications might show strange behaviour too, like missing menu borders etc.
Thunar falls back to GTK_STOCK_FILE these days.