Hi there
I have almost same problem with logging to Pinterest.
Actualy Opera mini wont open Pinterest as web page.
Instead opening as web page Opera mini opening Pinterest through Pinterest app.
It wont let me choose or give me possibility to open as web page just redirectly to Pinterest app.
I don't have possibility to save pages where I have been as my favorite pages.
If I try to uninstall Pinterest app then wont open Pinterest at all.
I try everything, clean data, clean chache, uninstall Opera, uninstall Pinterest app, nothing helped.
My standard browser work fine with that and Opera mini also working fine until couple of days.
Can anybody have solution or answer for this?
Thank you.