This happens because for a moment when you move to the content you are going out of site of the element that you are hovering and the tooltip content (you can see if the mouse goes through the callout arrow it will remain opened).
Basically there is no hideAfter
option that would be helpful to keep the tooltip opened, I can suggest you to share this as an improvement idea on the feedback portal where more people can vote for it:
Currently the only work-around I can suggest is to set the autoHide
option to false.
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