Background erase of debug variable panel was disabled for some reason, and it not anymore compatible with EVT_PAINT based refresh. It was leaving traces behind when removing traced variable. Fixed.
<?xml version='1.0' encoding='utf-8'?>
<BeremizRoot URI_location="LOCAL://">
<TargetType/>
<Libraries Enable_SVGUI_Library="true" Enable_Python_Library="true"/>
</BeremizRoot>