Can you share what your setup is like? I have bitwarden_rs self-hosted with Caddy in the front doing TLS termination and proxying the request to Bitwarden_rs and haven't experienced any issues for more than a year and half now. There are many ways in how Caddy can be configured (e.g. maybe even just keeping the certs updated, but not serving any HTTP requests [0]). Feel free to drop a thread on the Caddy forum and we can help you out!
[0] https://caddy.community/t/using-caddy-to-keep-certificates-r...