Empty paragraphs getting inserted when justify button is clicked

[Peter Tracey]

With the following HTML clicking on any of the text justify buttons leads to the editor freezing, then when Abort Script (A script on this page is causing Internet Explorer to run slowly...) button is pressed viewing source reveals hundreds of empty paragraphs (<p style="text-align: right">&nbsp;</p>) inserted before the table.

Steps to reproduce:

1. Use HTML provided below
2. Select all (ctrl-a)
3. Click right justify button

Editor will freeze and after a while abort script dialog will pop up.

4. Click yes
5. Click on the Source button, notice hundreds of p tags

Source that has this problem:

<FONT FACE="arial,sans-serif"> <BR><BR> <CENTER><B>ASDF</B></CENTER> <TABLE BORDER="1" CELLSPACING="0" WIDTH="100%"> <TR> <TD><FONT FACE="arial,sans-serif"><B>ASDF</B></FONT></TD> <TD><FONT FACE="arial,sans-serif"><B>FDSA</B></FONT></TD> <TD NOWRAP><FONT FACE="arial,sans-serif"><B>ASDF</B></FONT></TD> <TD NOWRAP><FONT FACE="arial,sans-serif"><B>FDSA</B></FONT></TD> <TD NOWRAP><FONT FACE="arial,sans-serif"><B>ASDF</B></FONT></TD> </TR> <tr><td nowrap><FONT FACE='arial,sans-serif'>ASDF</FONT></td><td><FONT FACE='arial,sans-serif'>FDSA </FONT></td><td><FONT FACE='arial,sans-serif'>39</FONT></td><td><FONT FACE='arial,sans-serif'>1</FONT></td><td><FONT FACE='arial,sans-serif'>0</FONT></td></tr><tr><td colspan='2' align='right'><FONT FACE='arial,sans-serif'><b>Total </b></FONT></td><td><FONT FACE='arial,sans-serif'>39</FONT></td><td><FONT FACE='arial,sans-serif'>1</FONT></td><td><FONT FACE='arial,sans-serif'>0</FONT></td> </TABLE> <BR><BR> </FONT>

[Wojciech Olchawa]

Confirmed with IE 6.0 IE 7.0 and FF2 (in FF2 the browser doesn't respond)

[Frederico Caldeira Knabben]

Probably related to #1717.