[asherkin]

The kerning is definitely quite a bit tighter in Firefox Nightly than in Chrome, but I do not see what you are seeing.

I'm getting the same font in both browsers (Verdana), maybe check using dev tools what font you're ending up with (maybe you've accidentally deleted Verdana - in Chrome it is at the bottom of the Computed tab when you have a post's div selected, and in Firefox there is a separate Fonts tab.

But it is definitely unrelated to any changes we've made - I just swapped out the icons.