User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.3) Gecko/20090910 Ubuntu/9.04 (jaunty) Shiretoko/3.5.3 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.3) Gecko/20090910 Ubuntu/9.04 (jaunty) Shiretoko/3.5.3 When the content of a contenteditable element is, for example: <p>foo</p><p>bar</p> and the cursor is placed at the end of "foo", hitting delete key has no effect when it should result in moving "bar" to the same paragraph, such as: <p>foobar</p>. Note that backspace at the beginning of "bar" works perfectly fine and does the expected merge. Reproducible: Always Steps to Reproduce: In a local file or in the editor demo at http://www.mozilla.org/editor/midasdemo/ 1. set the following html content: <div contenteditable="true"><p>foo</p><p>bar</p></div> 2. open file in browser or switch to editing and place the caret at the end of "foo" 3. hit the delete key Actual Results: nothing happens Expected Results: "bar" should move on the same line as "foo" and the html code should now become: <div contenteditable="true"><p>foobar</p></div> This reproduces for all kind of elements, not only paragraphs (2 consecutive lists for example are not merged on delete in the first one for example, deleting at the end of a list followed by a paragraph does not move the text in the paragraph to the list item, etc), while backspace at the beginning of the next item works correctly. I encountered the bug in the 3.5 Firefox version, and it doesn't reproduce on Firefox 2.0 nor 3.0.

I couldn't reproduce the problem with the steps you provided, maybe it's fixed on trunk? Could you try to reproduce the problem with a nightly build from here: http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-trunk/ It sounds like it's the same as bug 502259, which is fixed on trunk, in the upcoming FF3.6 beta and in the upcoming FF3.5.4.

Hi Chris, indeed it's a duplicate of bug 502259 (sorry for the duplicate -- I did search it I just didn't find it) which I cannot reproduce on the nightly build you indicated. However, the usecase discussed in comment #34 from that bug, *is* indeed a regression from 3.0. At least my 3.0.14 on ubuntu (installed from the ubuntu repositories) does handle the delete at the end of the list item ("two") correctly. Also, the behaviour between a list and a paragraph, for example, is a regression (delete at the end of a <p> before a <ul> -- 3.0 used to pull up the first list item content in the paragraph, nightly 3.7a1pre you indicated just moves the caret in the list and subsequent deletes remove the content in the list). Should I move this discussion in the comments for 502259?

forgot to mention, the cases in the file should be studied for hitting delete at the end of "foo".

confirmed on FF 3.5.4

User Agent Mozilla/5.0 (X11; Linux x86_64; rv:49.0) Gecko/20100101 Firefox/49.0 Build ID 20160526083057 Works for me on latest Nightly (49.0a1). I tested on Ubuntu 15.04 and Windows7. If anyone can still reproduce the issue on a current build fell free to reopen the bug.