Duplicate style node added hundreds of times

[rcmarron]

Hey everyone,

We've been having an issue lately where style nodes get added hundreds of times to a recording, and it causes the recording to become massive.

I haven't figured out how to reliably reproduce the issue, but it happens occasionally on our web app (app.posthog.com) and on several of our customer's web apps. I can't share the entire recording because it's massive and includes PII, but here is a gist with a subset of the snapshots: https://gist.github.com/rcmarron/d473fc0e5aeae281fffd978d6cc121a6

A couple of notes/thoughts:

• I've only seen it happen when really large nodes are added, but that's not to say it never happens with smaller nodes.
• I'm wondering if adding nodes to the addedSet is slow/async when the node is large, so when the MutationObserver sends duplicates, they aren't properly de-duped?

Let me know if I can share any more details

Thanks!

[Yuyz0112]

Thanks, for the report, going to debug this.

[rcmarron]

@Yuyz0112 I think I have a consistent repro for this issue.

If I use this Chrome Extension: https://help.getguru.com/en/articles/4680811-chrome-guru-browser-extension and open almost any website and run rr-web on it, it happens.

If you look at the full snapshots that are produced, you should see lots of duplicated large style nodes that start with the class name .SigninBlurb.

Thanks, and let me know if I can provide any more details or help at all.

[rcmarron]

Looks like this commit fixed this: #866 🎉

Closing this issue