When double-clicking a file in Finder/Explorer and choosing "yes" or "no" in the "Restore session" dialog, the file is not opened

To Reproduce
Steps to reproduce the behaviour on macOS:

1. Open one instance of MuseScore and open a score
2. Make it crash (for example: control-click its Dock icon, hold the Option (Alt) key and click "Force quit")
3. Now, double-click a MuseScore file in Finder (or equivalently: drag the MuseScore file to the MuseScore app icon in the Dock)
4. The "Do you want to restore session?" dialog pops up
5. Choose "Yes" or "No"

Expected:
When choosing "Yes", both the files from the previous session and the newly opened file are opened;
when choosing "No", only the newly opened file is opened.

Actual:
When choosing "Yes", only the files from the previous session are opened, and the newly opened file is ignored;
when choosing "No", nothing happens.

Platform information
Reported on macOS; reported on Windows in #19167; probably relevant on other OSs too

MuseScore version
Last checked in 4.4 (master)

Start by reproducing the failure through Finder/Explorer or by dragging a file to the MuseScore Dock icon, then trace how the “Restore session” dialog handles the pending file-open request. Done means choosing “Yes” opens both the previous session files and the new file, while “No” opens only the new file.