I want to change the content of the GIMP menus to make it a simpler application and hide all the advanced stuff that I never use.
Is it possible to do this via a theme or does it require creating a custom build from source?
You can try to edit the menu definition XML files in
The key file for the application menu is
You will not be able to get everything this way - for example, menu entries created by plug-ins will still show up. But if you do not want a plug-in to show up there, you probably do not want it in your GIMP at all, either.
Please note: changes in these menu definition files affect all users of your system.