Follow these steps: 1 - Follow the link provided (Wikipedia). 2 - Scroll down to the next-to-last line of text in the text area (it says "[[nl:WebKit]]"). 3 - Triple-click on that line of text to select it. 4 - Press delete on your keyboard to delete it. The line gets deleted, but two things are wrong: 1 - The last (empty) line gets deleted together with it. It shouldn't. 2 - A space gets added to the new last line (in this case, "[[it:WebKit]]"). It shouldn't.
Forgot to say that it's a regression and that it happens in the nightlies (with native text areas). The version I used is r18765.
Anyone can confirm this?
This bug has been fixed in the latest nightlies.