[cast] web-app-cast extension doesn't work with firefox, webkit and headless chromium

[saw-jan]

web-app-cast extension doesn't work on these browsers:

• Firefox (❌)
• Webkit (❌)
• Headless Chromium (❌)

Only works on these:

• Headed Chrome (✅)
• Headed Chromium (✅)

Steps to reproduce

1. Run ocis
2. Open "https://host.docker.internal:9200" in Firefox and Webkit browsers
3. Upload a file and check the "Cast" file-action from from the right-click context menu

Error logs:

👉 There are no other required requests to fetch cast related files (❌):

In headed chrome (works ✅), there are these requests:

Actual behavior

No "Cast" context menu

Expecetd behavior

There should be a "Cast" file context menu

[LukasHirt]

Firefox (❌)
Webkit (❌)

Aren't these two expected? Webkit has AirPlay instead of Chrome cast. No idea if Firefox even has anything...

[saw-jan]

We can skip in those browsers if that's the case, but we need the test to run with headless chromium.