My display is of 144 dpi and resolution is 1920x1080. I can see that the text in the menu bar and title bar is displayed properly; but the content is very small. Let us consider a few examples.
Inspecting 'Mail' tells me that font size is 13px.
This image clearly shows how small the content text size is. I found the text on this page has font size defined as 0.812em.
This website shows content in a reasonable size on my display. It has font defined as <font size="+1">.
I understand that web content can get fonts from two sources: the client system and the web. I have 144 dpi fonts installed on my system and web fonts also provide 144 dpi fonts. So, I want to know how I can make firefox use 144 dpi fonts for all content.
It is strange to me that Firefox's debugger shows fonts in reasonable size while Firebug shows fonts that are too small.
Following are two images of the same region of screen, one with firebug and the other with firefox's own debugger, for comparision.