image file missing
This is probably not very important. When starting gimp 2.10.26 in the terminal, I got these errors.
/home/bernard/opt/gimp/share/gimp/2.0/themes/Dark/gtkrc:1327: Unable to locate image file in pixmap_path: "ui/gimp-button-prelight-white-border.png" /home/bernard/opt/gimp/share/gimp/2.0/themes/Dark/gtkrc:1330: Background image options specified without filename
gimp was compiled from source on Ubuntu-20.04.
I got the same errors in Archlinux where gimp 2.10.26 was installed from AUR.