I'm using Cloudflare for my domain and have an Universal SSL enabled on the website. All traffic is going over SSL like it should. Although whenever I enable the SSL checkbox in the settings I can no longer access the website and get the error "The page isn't redirecting properly".
Additional I cannot check-out in my webshop when using SSL. I use the one-page-checkout and the buttons to go to the next step aren't working and they send me back to the shopping cart page.
I've noticed that I can only check-out if I use http instead of https (after disabling the rewrite options etc. in Cloudflare to allow non-SSL traffic).
How do I debug this issue properly of maybe this behavior rings a bell with someone?
Using v4.50.2 on Ubuntu.