I tried to build a T-Flip Flop for a door and wanted to test it but it didn't work, so I build anotherone outside of the system to avoid failure due to any other redstone and it didn't work either, so I tried another direction and that time it worked.
To reproduce the bug yourself, you can just follow the screenshots
Environment
Windows 10
Intel Core i7 8750h
Nvdia Geforce GTX 1060
16GB RAM
Minecraft is on a NvMe M.2 SSD installed
Hi there!
Does MC-11165 describe your issue?