[scofield272]

it's like that :
step1 : https://ibb.co/fOZZAx
step2 : https://ibb.co/c1QwOH
step 3 : https://ibb.co/doU1qx    (the .mkv displayed in the strm file)

 I see from your options that you are using the stable rather then testing, since there is no save TV/Movie STRM option.  Regardless, since the file doesn't have a year in it, it would have been detected as a "other" and it wouldn't have had it's file extension stripped off.

I'll add an option to explicitly let the user to strip the extensions off 

 you the best