It looks like Sync will only work with official Chrome starting two months from now. [1] It is understandable to some extend, perhaps to guard against malicious applications using unofficial (non-Chrome) API keys and tricking users to log into their account. This argument doesn't hold much ground in the context of trusted builds like our chromium package, but I doubt Google would bother to work with us (i.e.: each individual Linux distro) on this to find a workable solution going forward.
This is intended as a heads-up; I am not sure what we're going to do yet. [1] https://blog.chromium.org/2021/01/limiting-private-api-availability-in.html
