Same experience on our side. I did speak to a support tech at CF and that person believed me when I told them they have a bug in their http2 implementation, but the development team at CF completely ignored our findings.
We had similar random Cloudflare 520 errors that Ken from Driven and I probably put 100 hours into solving. We tried about a dozen optimizations with no change in the frequency of the 520s.
When we turned off Cloudflare "Speed=>Optimization=>HTTP/2 to Origin", the 520 errors completely went...
I want to feature a thread from a sponsor in a widget on the sidebar. The point is to bring users eyes to the fact that they have a chance to ask the sponsor a question about their product.
Thanks for your help.
Ken at Driven2 Services (MySiteGuy) just completed a complex conversion from UBBThreads to XF. Our forums https://www.bobistheoilguy.com/forums/ have about 5.5 million posts and were running UBB for over 20 years. You can only imagine the character set issues and other problems we had. Ken...