mastodon.social is one of the many independent Mastodon servers you can use to participate in the fediverse.
The original server operated by the Mastodon gGmbH non-profit

Administered by:

Server stats:

373K
active users

How to migrate from one Mastodon server to another without losing followers:

1. Sign up on new server
2. On NEW server: Go to Account -> Moving FROM another account
3. Enter old account's handle
4. On OLD server: Go to Account -> Moving TO another account
5. Enter new account's handle and submit

Scott.social

@Gargron One of the biggest complaints/warnings to possible new Mastodon users is that any instance can disappear and you lose everything (followers, etc). It is surprising that this has not been addressed with a migrate export/backup feature. ie. let people plan ahead or do it automatically between two instances (sync).

@Scott.social
You could save contacts as a simple list.
You could also try hubzilla nomadic identityw which does solve the problem described.