Bugzilla

(In reply to Jeroen Baert from comment #77)
> Some new reports of this popping up: https://www.reddit.com/r/firefox/comments/zyzsk6/high_cpu_usage_from_windows_defenderantimalware/
> 
> I'm personally running Win10 22H2 Build 19045.2604, all latest updates and I encounter this problem too.

Can you confirm if `MsMpEng.exe` behaves more reasonably after navigating to `about:config` and changing the following preferences:
- set `javascript.options.baselinejit` to `false`;
- set `javascript.options.wasm_baselinejit` to `false`;
- set `javascript.options.wasm_optimizingjit` to `false`.

If that doesn't solve the issue, you might be experiencing a different issue from the one mentioned in comment 82.

(In reply to Jeroen Baert from comment #77)
> Some new reports of this popping up: https://www.reddit.com/r/firefox/comments/zyzsk6/high_cpu_usage_from_windows_defenderantimalware/
> 
> I'm personally running Win10 22H2 Build 19045.2604, all latest updates and I encounter this problem too.

Can you confirm if `MsMpEng.exe` behaves more reasonably after navigating to `about:config` in Firefox and changing the following preferences:
- set `javascript.options.baselinejit` to `false`;
- set `javascript.options.wasm_baselinejit` to `false`;
- set `javascript.options.wasm_optimizingjit` to `false`.

If that doesn't solve the issue, you might be experiencing a different issue from the one mentioned in comment 82.