Pause page load animation while nav menu is engaged

I have a popup ad which is triggered by page load with a delay of 8 seconds. It looks odd if this popup appears when the user is in the nav menu, so I’d like to know if there is a way that I can pause that page load interaction when the nav menu is active, and resume it when nav menu is closed. Open to any ideas.

One idea I considered is to simply add an interaction which hides the popup element when the menu is triggered, and unhide it when the menu is closed. The main problem with this is that I don’t want the popup appearing every time the nav menu is closed. I’d like it to appear once, 8 seconds after page load (or later if the nav menu is opened in that first 8 seconds), and then when they close it (with close button interaction) be hidden for the rest of the session.

My gut tells me it’s probably not possible but I’d love to be proven wrong.