Version:           3.3.2 (using KDE 3.3.2 Level "a" , SUSE 9.2 UNSUPPORTED)
Compiler:          gcc version 3.3.4 (pre 3.3.5 20040809)
OS:                Linux (i686) release 2.6.8-24.5-default

To reproduce...
Close all instances of Konqueror, open a new instance, load a bugs.kde.org bug report - fx this one - and enter some text into the "Additional Comments" field. Now using MB1 select some of the entered text, let go of MB1 and press MB3 to get the expected popup with the "Copy" item.
At this point konqueror freezes. The popup does not show. Also, launching a new additional instance of konqueror does not fully render. Starting other apps like konsole and kcontrol show no problems. CPU utilization is normal. The freeze lasts 15 sec after which the MB3 popup does show.
For another place where I initially had the problem goto
http://news.bbc.co.uk/2/hi/talking_point/default.stm and
click on any of the blue headlines in the upper half of the page. In the right margin of the page that shows is a comment field that exhibits the same problem.
I'm on SuSE9.2 with SuSE's KDE3.3.2Level"a".