When you hover over a buff on the default WoW buff tracker, it shows you the tooltip alone. But when you hover over a buff on the Raven buff tracker, it shows you a tooltip, and it also shows you the icon twice. I'd like to request that an option but added for this functionality.

Sorry for the late response, I have been unwell.

In default WoW, the tooltip looks like this:

I suspect you have another addon running that is manipulating the appearance of tooltips. Can you test this by disabling all addons except Raven?