Created attachment 93640 [details]
To reproduce, open the attached TestCase1 and follow the instructions.
This also breaks caret visual positioning, caret keyboard navigation (Left\Right keys) and as shown in TestCase2, also breaks caret navigation using the Up arrow key.
a similar LTR issue was fixed recently in Bug 59968.
Confirmed with Windows Safari using WebKit nightly r86547
Relevant chromium issue: http://crbug.com/82774
Created attachment 93641 [details]
TestCase2 (up arrow caret navigation)
while it seems that the issues shown in TestCase1 has "always" been there (i reproduced the issues using a chromium build dated March 2010),
the up arrow issue (TestCase2) is a regression which happened between r84685-r84639
so i am guessing that it's the fix for bug 49508 (http://trac.webkit.org/changeset/84659)
might still be the same issue though...