I'm using a flatpak app whose desktop notifications I find useful in general, but too loud and annoying to endure all day long. It's an electron app showing up as "Chromium" in my OS's sound settings so I can't disable the audio for it there.
That's why I want to know if there's a way to intentionally run flatpak applications without any audio output
Details about my problem:
I'm using Microsoft Teams for work on Ubuntu 22.04, but the official PWA client does not support 'meeting started' notifications anymore. That's why I'm using it in combination with an inofficial teams client that's available on FlatHub which still has working notifications for when a meeting starts, but the option to turn off notification sounds doesn't work there, and the notifications are unbearibly loud compared to the actual meetings.
Hence I'd like to disable the audio of the inofficial client entirely while using the official client for joining meetings.
I tried to disable the inofficial client's audio through Ubuntu's Sound settings, but since it's a electron application it just shows up as Chromium there, just like my browser Vivaldi, and I can't figure out how to disable the audio in one, but not in the other.