Thanks for posting in the Community, @matt30. I can provide clarification on QuickBooks crashing when opening a second tab.
There currently is a known issue with the QuickBooks Online app when opening up a new tab. The engineers are aware of this and working diligently to resolve it.
You can be added to the list of affected users and receive email updates about this as soon as they become available by contacting the Phone or Chat Support team. Here's how you can reach them:
Should you not see the option for Get a callback, you can toggle it by entering Support in How can we help?.
The following is a quick video to serve as a visual example:
You can expedite this process by referencing INV-31308 to the agent as it's the ticket that the engineers are using for this.
I appreciate your patience while this is being worked on with the app. Please let me know if you should have any questions or need further assistance.