1. Paste several lines of js inside Scratchpad.
2. Put the caret somewhere near the end, and use Ctrl+Shift+Left to extend the selection.
3. When you have selected a few lines, start pressing Ctrl+Shift+Up. The selection isn't extended towards up, it seems that part of it are unselected at the bottom.
Confirmed. Still a bug in the latest upstream Orion.
Kevin: did you file a bug upstream? If not, I can file it.
I haven't filed this upstream and I'm having trouble reproducing this. If you can see the problem happening, then please do file it upstream.
Did some testing on Mac (thanks to Rob!) and on Win7. It seems only Linux users are affected. Fix should be easy.
This is now fixed by bug 697407, as well as upstream. QA will verify.
This is VERIFIED on Build identifier: Mozilla/5.0 (X11; Linux i686; rv:10.0a1) Gecko/20111102 Firefox/10.0a1