Preview stalls on iOS

[jeremyszym]

Describe the bug

On iOS the prevew stalls.

The first frame shows then it pauses. You can resume the display by scrolling down slightly.

The issue was encountered at Glasgow and by @fabienlombard

Rerpoducible on iPad with both Chrome and Safari

Technical details

On the dashboard the preview is currently embedded in an iframe. iOS is very aggressive with iframe and pauses the webrtc stream in ours. @sonnyp couldn't find a workaround in HTML/JS/CSS or in iOS/Safari settings.

[sonnyp]

The solution is to stop using an iframe. I propose to delay this after v2026 and after we move away from node-red.

/preview can be used in the meantime

[sonnyp]

@jeremyszym to test if this is fixed on main with the office ipad

[jeremyszym]

16th march : test preview on the Ipad with Level mesure (updated) and the usual frozen preview bug is still present.

[sonnyp]

We agreed that iOS support can wait until after v3 - in a software update.

@babo989 solution for glasgow was not ideal as it was re-encoding the stream in mjpeg which essentially "kills" HD preview and zooming.