Not getting encryption on files in my vault

I’m moving to Cryptomator from Boxcryptor and it doesn’t seem to work at all. I created a vault on Dropbox, just like I had via BC. When I added files in BC, they were encrypted on my computer (macOS) and looking at them on dropbox.com showed that they were unreadable in the cloud, as I expect. However, if I create a vault in Cryptomator and add a file to it, the name and contents are fully visible on dropbox.com. Why aren’t they encrypted? What am I doing wrong? Thanks.

Hi. Please make sure that you place the files you want to encrypt in the virtual drive that appears as soon as you unlock your vault in your Cryptomator app.

Do not place your files in the folder that is named after your vault and contains the masterkey file. This is where Cryptomator stores your encrypted files, and this folder is what you sync with your Dropbox account.

Or in other words: Vault is not encrypted - #2 by Michael

Please watch this Cryptomator Tutorial: Get Started - YouTube
And have a look at the documentation.