Shortly after the update to 1.5.0.2 (no option to say no - just a dialogue that said "Firefox has been updated. You must restart it now. OK" while we had a bunch of tabs open...) frequently (a dozen times last night) single line text fields on multiple sites refused to accept input. Clicking within them or tabbing would not get the cursor to appear and no text appeared anywhere if we just started typing - hoping it was a cosmetic issue. Page reloads and emptying the cache did not work. Only quitting Firefox and re-opening the page would let us enter text once this happend.