What are the widget replacements requiring opt-in?

[Mikaela]

From Privacy Badger Puts You in Control of Widgets I was aware of YouTube being opt-in by blocking it. I thought it was the only opt-in one, but reading bluetooth.com/auracast I noticed there was unreplaced Vimeo widget that I thought should have been automatic.

I tried blocking it, which let me to notice it works similarly to YouTube and looking around this issue tracker I discovered #2281 and yellowlist overriding widget replacing.

This leads to my question, are there other opt-in widget replacements than YouTube and Vimeo? Is there a list of them? I guess I could read src/data/socialwidgets.json and compare it to the yellowlist, but I don't think I am that curious regardless of being curious enough to ask and I am personally mainly annoyed by video embeds anyway.

[ghostwords]

Good question! All off-by-default widgets are widgets that we would like to make on-by-default after fixes and improvements to widget replacement. I think the list is pretty short at the moment:

• Google reCAPTCHA
• Vimeo
• YouTube

[Mikaela]

Thanks, I am definitely curious in trying all three. https://wonderfulengineering.com/googles-recaptcha-lead-to-819-million-hours-of-wasted-human-time-and-billions-in-profit/ was making rounds in some of my circles just yesterday

[ghostwords]

Cool, I block them all too. Two big issues with our reCAPTCHA replacement off the top of my head:

• www.google.com is used both for reCAPTCHA and innocuous JavaScript libraries. We should probably carve out some kind of path-based exception for the innocuous libraries.
• Sometimes reCAPTCHA is invisible. We should probably add "page-level" placeholders (not necessarily tied to any particular element, see also Block customer support chat bots by default, make it easy to allow them selectively #3057).