I have recently switched from Chrome to Firefox. All features that I used in Chrome seem to exist in Firefox as well, until I found out that there are no local overrides in Firefox? Some Information about this feature(it firstly appeared in Chrome's dev build in 2017): [https://www.youtube.com/watch?v=7-XnEMrQnn4&t=251s Local Overrides] Personally I found this feature very useful and convenient when debugging directly in your browser and immediately takes effect after a page refresh. I wonder if anyone else submitted a feedback or even had a discussion about this feature? I tried to send a suggestion about this feature but they temporarily disabled the submission form.