Proposal of strange file extesion for txt files.

When using "save as" for a file with an unknown extension it is proposing to save as text file. The native dialog proposes somewhat three entries *.txt (with dot) *.asc (with dot) *,v (with a comma). 

Apparently that comes from the mime types under "Tools">"Options">"Environment"

There is also some communication in the forum 
https://forum.qt.io/topic/88299/strange-extension-for-text-file-in-creator