To clarify, the 'https://appengine.google.com/_ah/loginform <https://appengine.google.com/_ah/loginform?.>' URL seen in the source is just the actual Google log in consent popup you took a picture of, and not the actual application that is attempting to access your email.
The actual application is attempting to access your Google email, and Google noticed this and presented you with this log in form to ask for your consent, but it has nothing to do with the actual requesting application. This authorization flow is called OAuth <https://developers.google.com/identity/protocols/OAuth2#webserver>. You can find out more about the original application that is making the request by recording a HAR file <https://toolbox.googleapps.com/apps/har_analyzer/>while you attempt to access your gmail in Chrome. The application/URL that is making this OAuth request should be listed in the HAR file right before the redirect to the Google log in 'https://appengine.google.com/_ah/loginform <https://appengine.google.com/_ah/loginform?.>' popup. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/b2dfca43-a7e8-4899-8e2b-7c4fd78230cf%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
