Let's work together and get this fixed, so you can go back to business, user980171.
When the tabs or buttons are not working as it should, your browser's cache might be causing this issue. Let's rule this out by doing some troubleshooting steps.
Here's how:
Open a private browser or incognito mode, and log in to your QuickBooks Online account. Private browser doesn't store cache.
Try to open a new tab. If it works, go back to your regular browser and clear the cache.