Prompt for VBA Project password after Excel closes with Dropbox Badge

Many of my excel projects are stored in a Dropbox folder through the Dropbox desktop app on PC, windows 7 and 8.1, Excel 2013, 2016. Dropbox recently updated to include Dropbox Badge when excel files from a Dropbox folder are open in excel. When Dropbox Badge was implemented I started getting a prompt for a VBA Project password after excel closes in some of my excel projects. This occurs in both versions of windows and both versions of Excel when all of the following conditions are met:

1. The workbook has a password protected VBA project
2. A userform is displayed sometime during the file's use.
3. The user closes the file after a change has been made and chooses to save the changes (saving separately before closing causes no error).
4. The file is stored in a Dropbox folder and Dropbox Badge is enabled.
5. (In some cases, having a msgbox prompt in the Workbook_BeforeClose event seems to cement the problem. Otherwise, it occasionally doesn't occur when closing.)

I've attached a simple file that consistently creates the error (its VBA Project password is "a"). It opens a userform in the Workbook_Open event. The Userform changes a cell value. The user clicks the command button to close the form. The user clicks to close excel. The Workbook_BeforeClose event shows a msgbox (though this can generally be removed and still produce the error). The user clicks OK in the msgbox. The user chooses to save changes to the file. Excel closes, and then the VBAProject Password prompt appears. Switching the Dropbox Badge setting from Always Show to Never Show alleviates the problem.

This problem is similar to that described in the microsoft knowledge base (https://support.microsoft.com/en-us/kb/280454) but doesn't involve a COM add-in (removing COM add-ins or setting their connections to false has no effect).

It has exactly the same symptoms as the problem with the Acrobat PDFMaker COM add-in several years ago (https://forums.adobe.com/message/5916268).

Is anyone else having the same problem? Is there anything I can do besides hope Dropbox implements a fix?

Thanks!

Sorry about that. My first time posting... I actually tried to be careful about the rules and guidelines but obviously didn't understand the cross-posting posting part. Thanks for pointing me to the info.