In practice, it was already removed half a year ago, but the description
 and cheatsheet entries were still there.

The migration intentionally does not use ConfigDB.get_by_params, since
this will break migration code as soon as we add a new field is added
 to ConfigDB.

Closes #2086

Making this configurable is misleading.

There's really no sound reason to turn this off anyway.

Improvements and fixes for http requests

See merge request pleroma/pleroma!2904

Rich media improvements

See merge request pleroma/pleroma!2944

Fix/2087 metadata

See merge request pleroma/secteam/pleroma!11

not needed options deletion

- fix for gun worker termination in some circumstances
- pool for http clients (ex_aws, tzdata)
- default pool timeouts for gun
- gun retries on gun_down messages
- s3 upload timeout if streaming enabled

* I added the option in config/config.exs
* created a new module lib/pleroma/user/welcome_chat_message.ex
* Added it to the registration flow
* added to the cheatsheet
* added to the config/description.ex
* added to the Changelog.md

Gun is still acting up.

This reverts merge request !2784

This reverts merge request !2677

Closes #1945

The new pooling code just removes the connection when it's down,
there is no need to reconnect a connection that is just sitting idle,
better just open a new one next time it's needed

This patch refactors gun pooling to use Elixir process registry and
simplifies adapter option insertion.

Having the pool use process registry instead of a GenServer has a number of advantages:
- Simpler code: the initial implementation adds about half the lines of code it deletes
- Concurrency: unlike a GenServer, ETS-based registry can handle multiple checkout/checkin
requests at the same time
- Precise and easy idle connection clousure: current proposal for closing idle connections in
the GenServer-based pool needs to filter through all connections once a minute and compare their
last active time with closing time. With Elixir process registry this can be done
by just using `Process.send_after`/`Process.cancel_timer` in the worker process.
- Lower memory footprint: In my tests `gun-memory-leak` branch uses about 290mb on peak load (250 connections)
and 235mb on idle (5-10 connections). Registry-based pool uses 210mb on idle and 240mb on peak load

https://git.pleroma.social/pleroma/elixir-libraries/linkify

Fetching the timeline is a bit heavy to do by default.