The KDE Typewriting Trainer has a keyboard layout editor which apparently is the only fully functional current GUI for creating layouts on Linux as a whole. I was almost finishing editing my layout when I realized that it exports the file as a custom .xml format, which can't be used by system.

If it allowed us to export the created custom layouts as a system layout for all programs, it'd be a perfect solution for people who need that. There are several forum threads on the web by people requesting an alternative to Microsoft Keyboard Creator, but the only options on Linux are to use a buggy ancient GUI that is no longer maintained (https://github.com/simos/keyboardlayouteditor) or to edit complex configuration files that require you to look up the Unicode key points or entity names for all characters you need, instead of just typing them.

Reproducible: Always