Use a custom Window object (aka: allow injection of rrweb from an iframe)

[samber]

First, thanks for this awesome project 👏

Currently, rrweb does not allow recording a user session from an iframe. This is a bit annoying for those who run rrweb in a third-party tool injected as a Javascript tag.

I would like to suggest a different implementation of #294.

#294 offers to look up the top Window object on the current page. This is a good start, but I would rather let the developer choose what Window HTML Element is the best: window or window.top or window.parent or window.parent.parent.[...] or document.querySelector('iframe').contentWindow...

PS: can anybody translate the doc to Chinese? 🙏

[samber]

Can be tested with stream.js script, with window: document.querySelector('#iframeResult').contentWindow added line 50.

Tested with the following page: https://www.w3schools.com/tags/tryit.asp?filename=tryhtml_iframe

[eoghanmurray]

OK I think building this on top of #294 is the way forward, however gonna query the core team for the best approach i.e. whether it's better not to assume that all users want the topmost window