How do I get rid of this error pop-up in WebStorm?

In the red circle:
I have an HTML file open, if I hover my mouse over almost anything, this thing pops up.
It's telling me there's an error even though there isn't.  This has been hindering my productivity, how can I get rid of it?

You can see me hovering over the li element, then within half a second, this thing pops up.