Oooh, I like this idea… I’ve thought about running vaultwarden but like you I pay for bitwarden premium because I think it’s critical for me and I like the service and want to see them continue. Using it as a backup, then I can still support them and run my own backup.
Planes that would land here typically use 100LL which contains lead. (LL stands for Low Lead). It’s not banned for aviation use.
There has been a push recently to use alternatives which don’t contain lead but most places still have 100LL as it’s a very long process to get things certified for aviation use.