Thee are currently a handful of web platform limitations such as WebGL, WebRTC, etc... The limitations are tracked in GitHub for each runtime. Here is the list of gecko-dev limitations.
We recommend limiting Replay recordings to 2 minutes in length — the shorter, the better. We are working on increasing the length of time Replay can record continuously and maintain performance.
Replay currently does not support recording applications with WebGL, and may experience errors. You can follow the GitHub issue here for updates.
Recording applications which use multiple windows is partially supported. When viewing a replay of a multi-window application, only graphics from one window will be shown, but you can still debug the code that executing in all windows.
Replay currently has an upper bound on the stack depth which means that some recursive functions will will cause Replay to crash.
Issues with a web application that would cause any other browser to crash, such as fatal errors or infinite loops, will also cause Replay to crash.
There are some known limitations with Replay when debugging applications that have certain criteria. The functionality of the replay will adjust for these situations to prevent crashes and unexpected behavior.
<aside> 💡 We recommend enabling Focus Mode to narrow down the number of hits.
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