If you scroll even 1/2 was through the first line of text in a textarea and then try dragging you can see that the drag-and-drop text is also cut in 1/2. Basically the top 1/2 of the text is missing, approximately the same distance down the text as you have scrolled through the first line.
Created attachment 15191 [details] Test case with just a textarea and 3 lines of text to allow a vertical scrollbar With this test case there is 3 lines of text to allow a vertical scroll-bar. After scrolling 1/2 way through the first line try highlighting some text and then dragging it. You will notice that only a portion of the text is visible equivalent to the amount that you had scrolled down through the first line. If you scroll past the first line the drag-and-drop text disappears entirely.
This is at-least affecting revision 23747. However charlesg was making it sound like it is also affecting S3b2.
Confirmed with a local debug build of WebKit r23737 with Safari 3.0 (522.12) on Mac OS X 10.4.10 (8R218). This is also a regression from Safari 2.0.4 (419.3) on Mac OS X 10.4.10 (8R218).
Note that you must scroll the text area vertically by slowing dragging a highlight selection down until the first line of the textarea is only partially visible. The scroll bars don't appear on such a small textarea.
<rdar://problem/5290118>
It seems that the patch that mitz posted in 14329 has resolved the issue that I saw in textarea. It is possible that the crash reported in 14329 and the missing cursor were caused due to a buffer or other additional issue. I think that this bug can be considered resolved once that patch lands unless there is an additional issue that someone else has not spoken up about or has listed only in the radar.
*** This bug has been marked as a duplicate of 14329 ***