it seems to have become more frequent recently.
i've been experiencing the same on firefox and i've also heard other people report the same on firefox, which happened around the time of the firefox 129 release. i didn't see anything noteworthy in the release notes though that'd explain this. it seems like it might be related to enhanced tracking protection and cookie isolation.
this is a lemm.ee limitation, not a Lemmy limitation, so this is the wrong community.
if you look at the instance sidebar at https://lemm.ee/ you can see that it's 4 weeks.
Retaining old content has value
this 100%. this is exactly why i wouldn't recommend any communities to be removed if there is still content in there, worst case just lock it.
cleaning up communities doesn't make lemmy more active either. it may help to make active communities stand out more against inactive ones though.
cleaning up dead communities isn't a great experience as it is today.
admins could purge communities, but this can cause unexpected breakages with other activitypub software that is more strict about cryptographic verification, as purging a community erases all information about it from the local instance, including the cryptographic private key. purging a community also only removes it on the local instance, so other instances would still have a cached (although possibly marked as deleted) copy of it. this would be the only method that frees up the name to allow creating a new community under the same name later on. locally this would also remove all posts and comments associated in that community, but other instances may think that they have users subscribed to the community and may still have posts and comments in there. this also means if a new community is created with the same name again, the local instance will still not know about older posts, but users on other instances might see them still, and the local moderator might be unable to interact with them at all, e.g. to potentially remove old problematic content.
the next option is removing a community as (instance-)moderator action. this will only mark the community as removed without further impact. regular users won't be able to access the community on the local or any other instance anymore, but its contents are preserved in case it gets restored at a later point in time. the name is not released and there isn't even an error message shown when trying to create a new community with the same name.
another option could be to "take over" the community and delete it, which is the act of the top community mod deleting the community (not a moderation action). in this case only the same top community moderator can restore it. this behaves mostly the same as removing it.
none of these options are good to use. imo purging should be avoided in any case, and the other options both require admin intervention to release a community later on and have no user feedback in lemmy-ui at this time, at least on 0.19.5.
for communities entirely without posts it is probably ok to just remove them and restore and transfer them if someone requests them. for communities with content the next best thing might be locking the community, potentially locking all posts if it's just a small number, to prevent unmoderated new content in that community, and put up a pinned post asking people to reach out if they want to take over the community. otherwise, if the community was removed or deleted, all the posts and comments within them would also be taken down with the community.
for sure, but they're neither mentioned on https://join-lemmy.org/docs/users/02-media.html nor on the linked CommonMark tutorial.
It's not even just that. It seems that the extra @ acts as a separator, so you can't even autocomplete e.g. @threelonmusketeers@sh as that'll try to autocomplete @sh instead of taking the instance domain as part of the mention.
I've raised a GitHub issue for this now: https://github.com/LemmyNet/lemmy-ui/issues/2652
on firefox, if i type @gedal and click or press tab once it replaces the text with [@[email protected]](https://lemmy.world/u/gedaliyah) .
the behavior is the same whether i hit tab, enter or click the text.
it contains turtle and crazy
The ban appears to be caused by your post linking to a known blogspam site that has frequently been spammed to Lemmy in the past.
You can export/import your account settings on the settings page, which includes also the following data:
There is no way to associate content you have previously posted/commented with your new account however.
You might need to import the file multiple times to get everything imported.
account names cannot be changed.
you can only change your display name, which is available in the settings.
whether display names or usernames are shown depends on the interface/client and user settings where available.
the only way to change the username is to create a new account.