I appreciate the detailed information about the experience with adding new customers and not showing in QuickBooks Online (QBO), pdlasiter. We can take some troubleshooting steps to ensure your browser's cache is cleared. I'm here to provide the steps below.

First, let's check your Square app integration settings for any changes or updates. If everything looks correct, try clearing your browser's cache and cookies. This can resolve any issues with QBO loading incorrectly, which may prevent you from viewing or adding customers.
 

Let's start with accessing QuickBooks using incognito mode or a private window.

Here are the key shortcuts:

• Google Chrome: Ctrl + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + N
• Safari: Command + Shift + N

If this works, you can clear your browser's cache and cookies  and any temporary files running in your browser that may have caused the malfunctions. Otherwise, you can use other supported browsers to ensure QBO runs efficiently.

Furthermore, consult this article for comprehensive guidance on obtaining assistance with QuickBooks products and services.
 

Additionally, once you're ready to manage your transactions, refer to this article for guidance: Connect and manage Square transactions in QBO.

If you still encounter challenges in your software, don't hesitate to reply. We're here to help you.