Hello there, @DougF. I appreciate you sharing detailed information about the list of categories that aren't showing when you create a transaction in the Banking menu. Let me share some troubleshooting steps to fix the bug you've experienced.

The unusual behavior of the QBO system, such as categories not showing in the drop-down, can be attributed to the browser collecting excessive data from frequent page visits over time. To address this issue, you can try performing some troubleshooting steps to isolate the problem.

Let's try to access your QuickBooks Online (QBO) account through an incognito window to determine if the issue is related to your browser.

Here are the shortcut keys:

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

If it works, you’ll have to go back to your regular browser and clear the cache to improve the program's performance. Using other supported browsers is a good alternative too. 

Moreover, there are times the system auto-categorize transactions with similar bank details from one category to another once you've activate the Enable suggested categorization. To confirm this, you may follow the steps below:

1. Click the Transactions tab.
2. Select Bank transactions.
3. Click the small Gear icon and uncheck the Enable suggested categorization field.
   

I will share some resources that will guide you on how to categorize your transactions and set up bank rules in QuickBooks:

• Categorize online bank transactions in QuickBooks Online
• How to set and use banking rules for downloaded transactions.

I'm looking forward to having this sorted out. Feel free to leave a reply if you need further assistance in categorizing your bank transactions. The Community team always has your back. Have a good one.