Long ago I noticed the default font size in Firefox and Chromium for monospace fonts is much smaller than for normal text, which made code snippets on my website hard to read. I don't know why this is, but I applied
font-size:1.2em to them. It made them about the same size, and it looked much better.
But recently I was setting up Firefox on a new computer and realized in the font settings, I could see that normal fonts rendered in size 16 by default while monospace rendered in 12. Then I realized something: if a user customized their browser settings to fix this issue, then code snippets on my site display as much larger than normal text, which looks awful.
What I want is to only make the correction if the user hasn't done it themselves, but I don't know how that's possible. If I hardcode the font size as say
font-size:16px, then that will override user settings, which I don't want to do. I want people to be able to change their font size... but I don't want the code snippets to render smaller.