If Firefox is using an unexpected amount of RAM, report a bug by following the steps below:

1. Open about:memory in a new tab.
2. Click Measure and save...
3. Attach the memory report to a new bug
4. Paste your about:support info (Click Copy text to clipboard) to your bug.

If you are experiencing a bug, the best way to ensure that something can be done about your bug is to report it in Bugzilla. This might seem a little bit intimidating for somebody who is new to bug reporting, but Mozillians are really nice!

If you prefer not to open a bug, you can instead reduce the number of content processes used by Firefox to a lower amount by going to about:config and changing dom.ipc.processCount.webIsolated to a lower number.

Please report issues: https://firefox-source-docs.mozilla.org/performance/reporting_a_performance_problem.html

If you want to find the bug, you can run a mozregression to find what broke it (using 114 as your last known good release and 115 as your bad release).

Please reach out if you need help with this.

You can use your profile to test this pretty easily.

I just compared the behavior in both Chromium and Firefox on my machine, and as far as I can tell, they act the same.

Steps to reproduce:

1. Open a video: https://www.youtube.com/watch?v=erQ_9yEz0ls
2. Play the last 10 seconds
3. Click "replay" button in the YouTube player

What happens:

The buffer is cleared in both browsers.

What are you seeing that is different?

Please help, I cant watch videos!

You could always disable hardware video decode acceleration and continue to watch videos.