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SUMMARY
"kate" uses file association "other/hunspell thesaurus file" for a file extension of type "*.dat"; changing this association to "normal" and pressing "apply" causes a S/W crash

STEPS TO REPRODUCE
1. open a file with extension "*.dat", e.g. "test.dat", with "kate"
2. "kate" associates this file type with "other/hunspell thesaurus file"
3. using "settings > configure kate > open/save > modes & filetypes¨, and changing "other/hunspell thesaurus file" to "normal", followed by "apply", causes "kate" to crash

OBSERVED RESULT
crash of "kate" when trying to change a file association

EXPECTED RESULT
application of the newly selected filetype as default for the flle extension "*.dat"

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Ubuntu 22.04/Kate 21.12.3
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
change of file association works as expected when using the "kate" pull-down menus of the opened file, or by changing the file type displayed at the bottom right of the window