To get the mixed content fixer working, please turn off the force rewrite titles option in the yoast settings.
Unfortunately I need that option on.. Thats what I need help with fixing.
You can insert the wp_title() in your theme:
Otherwise, you’ll have to fix the mixed content yourself, and turn off the mixed content fixer in the settings.
For the 2nd solution, what title exactly and what does that do? A bit confused
My guess is you use force rewrite title because your theme doesn’t use wp_title(). If wp_title is between the <head></head> tags, WordPress will insert page titles there. Yoast will hook into that function to optimize the page.
So adding wp_title would make it possible to turn force rewrite title off.