Welcome to the Community, @steve176.
At this time, the only way to stop the ads pop-ups is to manually close it by clicking the X or No, thanks buttons. The ads in QuickBooks are designed to guide and suggest you how to optimize your QuickBooks Online (QBO) experience.
I can see how seamless your work will be if the ads pop-ups won't show when opening your QBO account. However, clicking on the X or No, thanks buttons will keep from showing up again.
For now, you can visit our blog site so you'll be able to get the latest news about QuickBooks and what our Product Care Team is working on.
Keep in touch if you need any more assistance with this, or there's something else I can do for you. I've got your back. Have a good day and stay safe.