Unable to save search

A recurring problem I've been having is that I am usually unable to save my edits, even if the query runs ok.  My typical workaround is to copy the entire query text, close the query, open it again, paste in the text and then it will save. However, I have been trying to add a parameter to this one query and no matter what I do, it just won't save.

I add the parameter, run the search to make sure it still works, then try to save, only to get the error "Unable to save the search".

Video illustrating the error:
https://youtu.be/Ydr5XROuAaw