How can I specify the Facebook permissions (aka scope) OmniAuth asks for DYNAMICALLY?
问题 This question is similar to How can I specifiy what access I need from my user's Facebook accounts when using OmniAuth? but has a caveat. I'm using OmniAuth to authorize Facebook users on my website. For regular login/registration, asking the user for standard Facebook permissions are acceptable. But there is a feature on my site that requires extended permissions (access to their Facebook photos). I want to only ask for the extended permissions for users when/if they use our site's Facebook