https://c.im has 5000 characters limit.
https://kolektiva.social (anarchist) has 10 000
https://infosec.exchange has 11 000 characters and formatting.
https://qoto.org has 65 535 character limit and other features, but some servers (including Universeodon and main British one - mastodonapp.uk) block it.
You also can't follow hashtags on qoto.org
Asked a few qoto users, you actually are able to add a hashtag view as another column.
I tried to find one that kind of aligned with my interest and didn’t have a crazy number of users like mastodon.social. Reading online about picking instances, the recommendation to pick a smaller instance came up numerous times.
Went with sunny.garden since it’s a creative/artsy/tech instance and it’s been great. My local feed moves at a decent pace with content I enjoy, but I could also see mostly everything else on the federated tab.
You can still decide to transfer your account later on, so starting on mastodon.social isn't too bad. https://guide.toot.as/guide/move-mastodon-server/#1-guide-configuration Even if i would suggest to change it, as it kind of beat the decentralization aspect to it, i believe ~80℅ users are just on this default instance. The official website has it's own list of suggested servers per interests and some rules here : https://joinmastodon.org/servers You can search via a minimum maximum character limit here : https://mastodon.help/instances/en
By default, Mastodon servers can access all other servers. It's just the admin who can decide to block other instances on a blacklist for all the users on the instance they use. You can also just block yourself instances or users if you want. As long you don't take a political, shitposting, or fascist one which are often blocked on a lot of instances.
Oh I didn't know that, I thought they were locked to the server like Lemmy. Ok then I'll just use masdodon.social for now until I know more about the rest.
host your own if you care about privacy
I’d say go for mastodon.social, you can always move if you later find one you like more.
I would join infosec.exchange of the ones mentioned. Or just join mastodon.social. It's not going anywhere and it's the default and it's likely going to be the most stable in terms of user experience and longevity.
Having said that, to a degree it doesn't matter? Just follow the hashtags that you are interested in as soon as you get there and it should create an instant active feed. And don't forget to tip your server (I recommend kicking in a buck or two a month to the server admins and same to the mastodon devs.)
Decentralised and open source social network.