Right now I can only see that the only way to track conversion through Google Analytics is with Goals.
And it only allows entering the thankyou page URL.
In my case, I track registrations, and I don't use a thank you page.
When user lands on my homepage, clicks on Social Login button and after Sign in they land on the homepage again (but now logged in).
I use a Wordpress widget that appears when the user is loggged in. And this is how I track conversions.
But for this, I need a Google Analytics conversion pixel.
So my question is, is it possible, and does Google Analytics have a conversion (goal) tracking pixel?
You can send an event to Analytics when user is logged, so you can set that event as conversion.