Those are temporary indexes that were created while the reindexing was working. Every time it crashed due to duplicates, it would leave at least one temporary index behind. You can tell by the name, which ends in ccnew, ccnew1, ccnew2, and so on.
You can get rid of them by entering Psql and issuing the DROP INDEX command.
sudo ./launcher enter app
su postgres -c 'psql discourse'
DROP index ‘<index name>_ccnew’;
DROP index ‘<index name>_ccnew1’;
And so on. Make sure you have a backup of the database first, make sure reindex isn’t currently running, and make sure that you only drop the _ccnew indices.
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