Fix lost audio track on safari

[SystemKeeper]

☑️ Resolves

• Fix iOS/macOS - Audio/video channel is deactivated on the server side after muting #6094

After lots of manual trying, it looks like the safari bug was introduced between 12.0.0-alpha2 and 12.0.0-alpha3. After bisecting the commit abe5633 seems to be the problem. It belongs to the PR #5660 which replaces disabled tracks with a null track to reduce the amount of data being sent. Reverting the commit above makes the problem #6094 not reproducible anymore in safari.
I don't know if there's a way to use https://github.com/nextcloud/spreed/blob/main/src/mixins/browserCheck.js in peer.js as well, currently I just used ua-parser-js directly.

Based on the additional safari check, this should only effect safari and no other browsers.

🚧 Tasks

• Check virtual backgrounds still working

🏁 Checklist

• 🌏 Tested with Chrome, Firefox and Safari or should not be risky to browser differences
• 🖌️ Design was reviewed, approved or inspired by the design team
• ⛑️ Tests are included or not possible
• 📗 User documentation in https://github.com/nextcloud/documentation/tree/master/user_manual/talk has been updated or is not required

[Antreesy]

I see the way like this: we can split this mixin into utilities (common) and composable (to use in components)

[ShGKme]

I see the way like this: we can split this mixin into utilities (common) and composable (to use in components)

We need neither mixin nor composable here. This functionality has nothing Vue-related nor anything reactive. No chance that "a web-browser will be changed during a process" =D

So we can make it an util.

[SystemKeeper]

So we can make it an util.

Maybe we could do that first and then rebase this PR on top of it? I would like to keep this PR as isolated as possible (Safari 😅...)

[ShGKme]

So we can make it an util.

Maybe we could do that first and then rebase this PR on top of it? I would like to keep this PR as isolated as possible (Safari 😅...)

I'll make a PR in 0.5h

[nickvergessen]

PR was closed by #11009 due to wrong comment. Reopening

[nickvergessen]

Needs a rebase now

[SystemKeeper]

Needs a rebase now

Will take care

[SystemKeeper]

Rebased on main.
Thanks @ShGKme for taking care of that browserCheck utility 👍

[SystemKeeper]

/backport to stable28

[Ivansss]

Tested and works 👍

[SystemKeeper]

/backport to stable27