Strange default zoom in Firefox 22.0

Question

I have a completely fresh installation of Firefox 22.0 on Windows 7 and I just opened a website.

The website appeared to be zoomed (fonts as well as images) so I hit

Answer 1

It seems that this behavior is caused by the fact that from version 22 Firefox takes into account the font size set in the OS (e.g. "125%" corresponding to 120dpi). There is some info on Mozilla support forums:

http://support.mozilla.org/en-US/questions/962945

http://support.mozilla.org/en-US/questions/963211

Answer 2

1) Type "about:config: in address bar
2) search for "layout.css.devPixelsPerPx"
3) change value of "layout.css.devPixelsPerPx" from -1.0 to 1.0