Brave (Chromium?) sync cryptographer error make it totally unable to sync but silently

Hi there, I got a pretty annoying, obscure and undocumented problem with Brave Sync.

I cannot get Brave Sync working, although it works perfectly fine with the same version on my Arch setups. When I try to connect Brave to my existing sync chain (already containing 3 devices) by entering the 25-words passphrase, it seems to work (no errors or warns at all) but looking closer in the sync settings section, I see no other devices of the sync chain. Obviously, it doesn’t sync at all.

I got these messages by trying to sync after launching Brave from the cmd :

[7615:7615:0905/193641.777425:ERROR:data_type_manager_impl.cc(35)] Bookmarks cryptographer error was encountered:
[7615:7615:0905/193641.777448:ERROR:data_type_manager_impl.cc(35)] Device Info cryptographer error was encountered:
[7615:7615:0905/193641.777455:ERROR:data_type_manager_impl.cc(35)] Send Tab To Self cryptographer error was encountered:

And this error is displayed a few times in brave://sync-internals after trying to sync :

Error: GenerateCryptoErrorsForTypes@components/sync/driver/data_type_manager_impl.cc:35, cryptographer error was encountered:

I thought about an encryption problem so I managed to get gnome keyring working and passwords stored within but it didn’t solved anything.

Just in case, I’m new to Nix and NixOS (started playing with it 1-2 weeks ago) so here my noob config files : https://gitlab.com/gfauredev/nixos-configuration that I manage with a bare git repo and symlinks (I know this isn’t the best way to do) :

ln -s ~/.config/configuration.nix /etc/nixos && ln -s ~/.config/gfaure1.nix /etc/nixos/host.nix

I searched for hours and I don’t have any idea of where to search so I ask you. What would you recommend to investigate, even if you don’t have the exact answer to this hyper-specific and probably rare issue ? Thanks a lot in advance.

I know brave’s builtin ipfs support doesn’t work because it uses a binary it downloads and manages on its own to do it, and the packaging doesn’t use a buildFHSUserEnv. The sync feature might be suffering from a similar problem? I don’t use that bit, myself.

Thanks for your reply.
Well, I will try to make a custom package with buildFHSUserEnv, but I have to learn more about nixpkgs before.

Same problem. Interestingly enough everything works fine if you create a new sync chain from the nixos device. I have no idea why but this is my solution for now. If you also can’t remove you current (not working) sync chain, try the button “Disable Sync (Clear Data)” here: brave://sync-internals/ .

Yeah I ended up doing that, but I wonder if this workaround doesn’t brings some security issues since the encryption might not work as intended .