1. Paste a relatively large JS file in Scratchpad. Select the first three lines.
2. Click on the scrollbar to scroll one page down.
3. Shift+PgDn. Scratchpad will scroll one page down, but the selected region is invisible.
It looks like Orion is not selecting as much text as would be expected given the scroll position. I tried this in a Firefox text area and in TextMate. Those two behaved slightly differently, but the selection was visible in both, which is important.
Filed upstream: https://bugs.eclipse.org/bugs/show_bug.cgi?id=358615
This is now fixed upstream.
This is now fixed by bug 697407. QA will verify.
This is VERIFIED on Build identifier: Mozilla/5.0 (X11; Linux i686; rv:10.0a1) Gecko/20111102 Firefox/10.0a1