I tried repling to your email through email@example.com but it kept bouncing. When you say "Can you click the Dropbox icon in your menu bar" I'm not sure where you mean. I've attached an image of where I think you mean but I cannot find the gear icon in the top right to choose“Quit Dropbox”. Would you please indicate where I find this Dropbox icon that has the gear icon?
Hey again @werd, apologies for the tardy reply here!
I wasn’t able to see the screenshot unfortunately, but I have added an image below of where you should see the Dropbox icon in your menu bar.
Dropbox icon in menu bar
If you aren’t able to locate the icon or can't quit the app from there, you can also try to Force quit the app if it is running on your device and then you should be able to go ahead with uninstalling it.