This one I just learned about. I didn't want Firefox going in 10% default increments when scaling a webpage up or down. And I didn't want to use another extension like Zoom, that can go in increments, so Google AI showed me this. It's not security related, but may be come in handy.
In about:config copy and paste toolkit.zoomManager.zoomValues in the search bar then clear out the numbers and copy and paste this in.
.3,.35,.4,.45,.5,.55,.6,.65,.7,.75,.8,.85,.9,.95,1,1.05,1.1,1.15,1.2,1.25,1.3,1.35,1.4,1.45,1.5,1.55,1.6,1.65,1.7,1.75,1.8,1.85,1.9,1.95,2,2.1,2.2,2.3,2.4,2.5,2.6,2.7,2.8,2.9,3
Click the check mark or keyboard Enter to save it. It will give you increments of 5%. Using Ctrl + 0 resets the page. I understand it can be further tweaked, but 5% works for me
