set_credentials error when logging in with neovim

[OZoneGuy]

Going through the setup guide in the README, I get this error when I run :SourcegraphLogin:

Failed to save credentials - Please report this error: set_credentials

At this URL: http://localhost:52068/api/sourcegraph/token?token=XXX.

I am using Firefox and on Arch Linux.

I tried disabling enhanced tracking protection, but still failed. It does create the token successfully.

Is there a place I can add the token manually, or do I need to add it as an env variable?

Please let me know if you need more information.