I followed the instructions on Bitwarden’s website and deployed Bitwarden in a docker container on a Linux host.
I set up an account on Duck DNS in order to have the domain point back to Bitwarden from outside.
At the very end of the process I got a message: “Bitwarden is up and running!” and I ran the command “sudo docker ps” and everything is showing as “healthy.”
Internally when I browse to my “vault” Google gives me a warning that I’m going to a dangerous site and if I “visit the unsafe site” it says “The site can’t be reached.”
If I try to browse to this outside my network it says “The site can’t be reached.” from the start.
When I try this step: “Congratulations! Bitwarden is now up and running at https://your.domain.com . Visit the web vault in your web browser to confirm that it’s working.” is where I get the malicious site warning.
I’m replacing the URL in the instructions with the URL for my vault.
I think what dwbit was saying was that if any of the words in your vault URL https://your.domain.com contain the word “bitwarden”, then it is common for the domain to end up on a blacklist (because it makes it look like it could be a phishing site).