If you click the cog for options on a shader node then you get a popup window of some kind, if you then move elsewhere and click on other things then that popup stays visible (you could have 10s of them open).
This seems like a simple UI mistake - popups should close when you click outside of them (or on another control), you should not need to click the (quite tiny) cog again.
A similar ‘mistake’ is repeated in the HDRP volume ‘Add Override’ control that can leave a popup open after leaving said volume, so maybe a core UI issue?