What steps will reproduce the problem?
1. Install Broker_Extractor from Zhinjio,
2. Show and hide the tooltip several times to have it recycling the cells.
What is the expected output? What do you see instead?
You could see icons in cells that should not display any image.
Please provide any additional information below.
One can add images to fontstring by using texture escape sequence (|T...|t, see http://www.wowwiki.com/UI_Escape_Sequences). It seems that theses images are not always properly hidden when the fontstring is changed. As LibQTIP cells are recycled, it means that a cell with a buggy remaining image may be recycled as a text-only cell. When that happens, the image is still displayed in the cell background.
I think this is a Blizzard issue. However I would like to experiment a workaround: detecting when the string contains a texture escape sequence and using two fontstrings (a text-only one and a text+image one). The two fontstrings would not be created unless need be.