Because of Mozilla Bug #45375, when you mouse over images with title-text, you can't always read it all -- it trunchates instead of wrapping. Since Firefox has had this problem for years, a whole bunch of people have gotten fed up and written extensions.
I don't really know who you bother at Mozilla to get this fixed, but in the webcomic community we've just given up and we all install the Long Titles extension.
So if you want to read the title-text on the comics in Firefox, that's where you should go.
edit: Replaced HTML with BBCode, oops.
