Looked like this
that's due to the browser/webpage and out of my control. Similar to selecting text you can highlight a whole game window in itch cause its embedded, typically by clicking and dragging from outside the game window to a spot inside or on the opposite side of the game window. Clicking should deselect it and remove the highlight, but webpages can be a bit finnicky with where it registers it. Maybe I should provide a downloadable version tho hmm