Please ask Sticky Password to support Vivaldi
I love Vivaldi and Sticky Password is the best password manager I've tried. Unfortunately SP doesn't officially support Vivaldi because its user base is too small. Please ask SP and Vivaldi to support each other.
My older versions of each work beautifully together, but I am updating both to latest versions and have my fingers crossed.
I have been in frequent contact with Sticky Password, including notifying them when the Vivaldi/SP combination keeps working after an update to either (which thankfully has been the case for a while) and even offering to pay SP to officially support Vivaldi (my offer was declined). The only way SP might decide to support Vivaldi officially would be if large numbers of customers requested it.