Is there any chat where threading is still enabled? Did you check all DM chats?
You can use this data explorer query to find all your chats where threading is enabled.
-- [params]
-- user_id :user_id
WITH memberships AS (
SELECT
uccm.user_id,
cc.id AS chat_channel_id,
cc.type AS channel_type,
cc.name AS channel_name,
cc.description,
cc.threading_enabled
FROM
user_chat_channel_memberships uccm
JOIN
chat_channels cc ON uccm.chat_channel_id = cc.id
WHERE
uccm.user_id = :user_id
AND cc.threading_enabled = TRUE
)
SELECT
m.chat_channel_id,
COALESCE(
NULLIF(m.channel_name, ''),
(
SELECT string_agg(u.username, ', ')
FROM user_chat_channel_memberships uccm2
JOIN users u ON uccm2.user_id = u.id
WHERE uccm2.chat_channel_id = m.chat_channel_id
AND uccm2.user_id <> m.user_id
)
) AS sidebar_name,
m.channel_type,
('/chat/c/-/' || m.chat_channel_id) AS chat_url
FROM memberships m
ORDER BY m.channel_type, sidebar_name