>>>>>When I was editing a message (in the lower pane), I selected some of the text and pressed CTRL-C to copy it. Immediately, the font on all UT pages turned to a very tiny size almost impossible to read...
>>>>
>>>>Try Ctrl+ to increase the font.
>>>
>>>Hey, thanks! :)
>>
>>Did it help?
>
>Yeah, but a single click changed it to a large font. Strange. I closed the tab in IE7 and logged in on another tab...

I think you can also do it with the mouse, I forgot the exact trick.