[Bug]: WARC files are very slow to load in Firefox

[Shrinks99]

What did you expect to happen? What happened instead?

When loading a WARC file in Chrome, records are processed at a reasonable speed. When loading the same file in Firefox it is wildly slow and pretty much not feasible to use as a result.

Step-by-step reproduction instructions

1. Obtain a WARC file of ~200-500 MB in size (tested with 500 MB) (if you need one to test, contact me!)
2. Attempt to load the file in ReplayWebpage in both browsers
3. Note the discrepancy in loading speed

[Shrinks99]

Note: If you're running across this issue and we haven't gotten around to fixing it yet (or are unable to do so) — it's on our radar obviously — consider using py-wacz to create a WACZ out of your archive for faster loading when delivering archived content to users :)