Setting comments on blocks with ctrl + K sometimes deletes the last line.
To reproduce:
Paste the following code into an empty document and select the text from after the last ENDIF (just after the F at the end of the line) and up to the start of the line before and press ctrl + K.
IF x = y
ENDIF
It's important that you have two (or more) <tab> characters before the ENDIF, otherwise it won't work.
Thank you so much for making this, so I can really reproduce it now!