Do you happen to have any plugins active like the save actions one?
Good point. I have one activated which - I'm using the German version - is called "Speicheraktionen". It came with Geany. This must be the one you are referring to.
Now, if I *disable* it, and try to save the file, and get the error pop up, the popup goes away.
This means that it is this plugin which causes the problem!
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