Hi Markus, (moving my query from irc here) 1) I tried to create a uitest for calc as a testcase for https://bugs.documentfoundation.org/show_bug.cgi?id=108881 . In that I load the document referenced in bugzilla which has an empty chart object. Then I close that doc, and open a blank calc doc, but the uitest throws an exception on running it. ( For now I have commented out code relevant to reproducing the tdf bug. ) The uitest case and backtrace shown are at https://pastebin.com/TbpfSJ8J 2) Another query is about debugging the uitest as explained in your blog https://mmohrhard.wordpress.com/2016/09/10/writing-a-libreoffice-calc-ui-test/ : is to run the uitest as shown in this script : https://cgit.freedesktop.org/libreoffice/contrib/dev-tools/tree/uitest/execute.sh I was trying to do that but seems there is no python executable in instdir/program in my debug build. Using system python does not seem to work. Thanks for your help. Regards, Dennis