I find that newer created sync chains on updated version of Brave so far work, when I try to use a old sync chain from over a year ago they do not sync well and are buggy.
When I tried to use my old sync chains I tried them on new devices that do not have any bookmarks on them and have never been apart of this sync chain. and all devices that were previously apart of the sync chain were wipped and no longer on the chain. Essentially no devices have used my old sync chain in months and those devices that did were wiped.
I still had the 24 wood seed to rejoin the sync chain and it was able to fetch most of my bookmarks from the sync chain but it did not sync well and was buggy.
Please make a feature to be able to delete a sync chain. The reason for this is privacy, I understand no one has access to these bookmarks of mine unless I share my 24 word seed but it is better to be able to delete this chain and all the bookmarks saved to the sync cloud than have them up there with a possibility that they can be compromised. The sync chain to my understanding is not a blockchain so to delete a sync chain and all of its bookmarks should be possible to impediment.
By adding this feature, people can delete their unused sync chains and help Brave save data since less unused data will be stored on the sync servers.