Troubleshooting Assistance with the Fastmail App

internic

I use the Fastmail Android app, which as been working great for me since I switched to GrapheneOS. But I use a Yubikey as my second factor for authentication, and recently that stopped working correctly; it basically fails immediately when I tell it to read the Yubikey. The 2FA does work correctly if I instead use their web app in Vanadium. When I try to use the 2FA there, it first brings up a popup that says "No passkeys available" and then allows me to select "use a different device" and then "NFC Security Key" or "USB Security Key". This pop-up and the subsequent choices never come up with using the stand-alone Android App. I think that the Android app is mostly just the webapp in a wrapper, so I'm guessing that this may be something about how Vanadium WebView is interacting with the Yubikey 2FA differently than when I'm just loading the web app in Vanadium itself.

I've contacted the Fastmail support folks, but they're assuming that I'm on stock Android, so they're asking me to ensure I've updated Google Play Services and Chrome Webview. I can see that the sandboxed version of Google Play Services doesn't have any updates waiting by going to the GrapheneOS App Store, but I have no idea how to verify that there are no updates of the Vanadium Webview pending.

I would welcome any tips about 1) what might be going wrong with the Android app vs. the web app, 2) how to do the equivalent of verifying there are no updates to Chrome Webview in GrapheneOS, or 3) how to gather additional diagnostic information that might be helpful.

fid03

internic I can replicate the issue but I haven't found a workaround that doesn't require outsourcing the FIDO functionality to some other app.

When I installed this app called FIDO Bridge https://play.google.com/store/apps/details?id=com.token2.fidobridge and enabled it in the Settings app > Passwords & passkeys, I was able to use a Yubikey to sign in to the Fastmail app.

(I also tried Passchain from the Accrescent app store, but it gave me a truncated error message about RP not being allowed from...).

DeletedUser928

Full disclosure: this is no help and I'm hung over like a canuc on July 1...

I've been a Fastmail user since 2005. Whatever Fastmail is now is not what what Fastmail was then. Faaaaaaa ...aaar from it. An Opera takeover here, a hostile union buyback there, Google finally doing imap and imap over tls, technically inept "prosumers" dictating tech trends (aka catering to the lowest common denominator, aka enshittification) there yet, and you get the apple focused sh;t Fastmail became.

Apparently their support lives up to the aforementioned expectations.

internic

I mean, so far they're going through some basic steps, which is reasonable, so I can't really criticize yet. I hadn't told them that I was using GrapheneOS, because, not having dealt with their support before, I was afraid that would provoke a knee-jerk "oh, we don't support that." So if I can figure out at least how to verify that Vanadium Webview is up to date then I'll let them know I'm on GrapheneOS and see where that goes.

internic

fid03 Thanks for that information! I probably won't go down the path of installing another app to handle FIDO just yet, but it's useful to know that that's an option. Presumably that indicates something about the specific nature of the issue, but I don't know enough about how FIDO works under the hood in Android/GrapheneOS to say what it means. For now my workaround is to run the web version as a progressive web app, but I'd certainly prefer to get just the Android app working properly again.

Maybe I should open a second thread in the forum just about checking the version of/checking for available updates to Vanadium Webview, since that's the current sticking point with Fastmail tech support.