Display of Overlays seems unreliable

But your problem is that you are not even getting the extension taskbar, which points either to the extension not being active, or something else going on that might be, beyond your control.

It’s weirder than that. What I saw yesterday was that sometimes (albeit occasionally) the extension taskbar would briefly flash our extension, but then it would disappeared again. At no point did the Overlay itself appear – at best just the taskbar, and then only occasionally and briefly (for less than a second). At no point was I able to find the extension listed as an iFrame in the browser inspector, suggesting it never loaded. Mind you the very same Overlay was working fine on other streams running at the same time. And also at the same time I was seeing data pipe in to our server from that streamer, suggesting for some viewers the Overlay was up and running for some but not for me.

As covered in that issue. Extensions can’t self open, only self close.

Yes, understood. That was very helpful in resolving that question. The reason I brought up the prior post is that then as now we were experiencing these inconsistent Overlay renders, where some viewers were seeing it, and others were not. Even my experience was mixed: sometimes seeing it render on those days, sometimes not. And that brief taskbar appearance: flashing on, then disappearing, was also a thing. (That’s what prompted the original question: about whether Overlays can auto open / close)

it could be ad/script blockers userside interfering, BTTV/FFZ extension blocking or something else.

Possible. Safari’s latest browser (released this month) has a new on-by-default tracker blocker. Considering I was able to see the Overlay play on other streamers’ channels suggests it’s not blocking our extensions’s iframe. We don’t have “trackers” but I don’t know for sure how Safari is defining what it detects. In any event we were testing with not only Safari, but also Firefox and Chrome, all on Mac OS

I’m saying if extensions are changed during a stream
existing viewers see the previous setup
new viewers see the new setup

That would make sense. I’ll try to confirm whether they made any changes mid-stream.

Thanks.