I can set firefox snap to download files without asking. Then I can use the Download manager to open the app. I download a .zip. Ubuntu 23.04. The handler for .zip is Archive Manager.
After download, I go to Firefox Download Manager, and select the file. Here, the behaviour of the snap is not quite correct. If I am using the Mozilla binary, the downloaded file open in Archive Manager, as expected.
In Snap Firefox, it does some kind of handoff to the gnome shell, but presents me with this dialog, asking me to choose between Archive Manager and Files.
This is what Gnome shows with I choose Open With… in Files"
So to me it seems like Snap is treating the Default App and Recommended Apps as peers, and it can’t decide between them, so it asks the user.
The correct behaviour is to skip this dialog, and use the Default App.
For convenience, I am using this site for download examples: https://www.learningcontainer.com/sample-zip-files/