Uber Facebook login redirect doesn't work on mobile devices

[corradio]

To reproduce:

• start playground
• connect to playground in iOS simulator (remember to enable popups in iOS safari settings)
• tap to connect uber
• press on facebook icon
• log in to facebook
• redirects to uber but doesn't go further

Also seems to happen on Android. Works fine from a desktop browser.

[corradio]

Simpler reproducible case:

• console.log the authorizationCodeRequestUrl L65 in OAuth2Manager.js
• use playground to connect uber
• copy link obtained from console.log
• open link using Chrome desktop in mobile mode (Galaxy S5) using debugger tools
• click on facebook -> no redirect after facebook login
• open link using Chrome without mobile mode -> works

After some digging I found that this error occurs:

which comes from a token verification code from uber after the facebook redirect:

I found that decodeURIComponent(n) yields {"query":"?breeze_local_zone=dca1, which obviously is a truncated JSON containing incomplete info.
n is coming from t.fbstate -- would that mean the facebook state returned is invalid?

..that's just weird as variable o is not even used.

@willtonkin have you seen such madness? This only happens when mobile mode is enabled (i.e. probably when user-agent changes)

[corradio]

@FelixDQ said:

It looks like this is a problem on Uber's side. Going directly to https://m.uber.com on a phone and trying to login with facebook also doesn't work.