Hmm, my uninstall.exe is older than yours for some reason. It matches up with this analysis: https://www.virustotal.com/en/file/f4df617014d1a7629482a4b4b83c27cea5f17460a6db50981ae2493534164c62/analysis/

I have to admit I don't know how to read all the details in these reports.

Where do you see that your file was unsigned?

If your on Windows, right click > Properties > "Digital Signatures" tab. (if there is not a signature, the tab wont display).

I dont have a linux box in front of me but would assume "right click > properties" would work as well...

Thank you for explaining about the missing tab.

This seems to be some kind of oversight. The "real" executable matching the "Original filename" can be found in

C:\Program Files (x86)\Mozilla Firefox

under the name

maintenanceservice_installer.exe

That probably should have been copied to the other folder and renamed Uninstall.exe, or maybe that in itself would invalidates the signature??

I'm not sure who can answer a question like this.