I added a deposit to the invoice, the deposit box shows up but the deposit to dropdown does not

I can share a way how we can rectify your concern about the Deposit to dropdown in QuickBooks Online (QBO), @mhobbs2022.

Before we start, are you adding a deposit through a receive payments option? If so, I have this one replicated to ensure that I provided the correct solution. Upon replicating, I could see the Deposit to field from the page.

To resolve this one, I'd recommend performing basic troubleshooting steps. In this manner, we can eliminate common errors in your company file. To start, please open your browser's private window. It isolates the cache, which is the common cause of a browser's unusual behavior. 

Here are the keyboard shortcuts to open a private browser:

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

If the option to add a deposit to is already visible, proceed to clear the cache in the browser to prevent this from happening again. An excessive amount of cached data may cause QuickBooks to perform oddly. If you have another supported browser, you can choose that instead.

Please let me know by adding a comment if you have more concerns about your QuickBooks interface. I'll be around the corner to lend a hand for help. Have a good one!