Re-sync with develop branch. Several things absent/missed.

lib/pleroma/conversation.ex

lib/pleroma/conversation/participation.ex

lib/pleroma/user.ex

lib/pleroma/user/query.ex

...pleroma/web/admin_api/controllers/admin_api_controller.ex

lib/pleroma/web/admin_api/controllers/user_controller.ex

lib/pleroma/web/admin_api/views/account_view.ex

...leroma/web/mastodon_api/controllers/account_controller.ex

lib/pleroma/web/mastodon_api/views/account_view.ex

lib/pleroma/web/router.ex

...0831114918_remove_unread_conversation_count_from_user.exs

...115854_add_unread_index_to_conversation_participation.exs

test/pleroma/conversation/participation_test.exs

test/pleroma/object_test.exs

...a/web/admin_api/controllers/admin_api_controller_test.exs

...leroma/web/admin_api/controllers/user_controller_test.exs

test/pleroma/web/admin_api/search_test.exs

.../web/mastodon_api/controllers/account_controller_test.exs

...mastodon_api/controllers/conversation_controller_test.exs

.../pleroma_api/controllers/conversation_controller_test.exs