Increase code font size in firefox developer tool

Question

How to increase code fonts in Firefox developer tools? I know that there is a zoom function but I want to set the font size only for the code.

Answer 1

This one works on FF 68 Linux with userChrome.css. I think inspector tools are now using CSS variables and the inspector tree itself is loaded in an iframe so none of the tweaks actually worked esp. with .CodeMirror classes.

You can find all the variables in this file (just copy paste below URL in FF to view source)

resource://devtools/client/themes/variables.css

For the userChrome.css part here's what solved it for me.

/* @namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul); */

:root {
  /* Text sizes */
  --theme-code-font-size: 13px !important;
}