I have two forums, one in 3.0.12 and the other in 3.2.1
I was able to spot this bug by moving all of my working custom BBCodes to the newer version 3.2.1 and at first I did notice some BBCodes didn't work until http in the codes were changed to https, but still, I have BBCodes that do work on 3.0.12 and not on 3.2.1 and still not sure why. When I found out that the ( = ) in custom BBCodes was working but causing the other BBCodes that they paired with to not work, I set up a new forum again to see if it was in phpBB itself and it sure is.
Below are screen shots of my custom BBCodes I'm testing this with.
Below is this Custom BBCode compared to 3.0.12 vs 3.2.1
Below is the preset BBCode in 3.2.1 that does the same thing, but works ???
My forum needs these custom BBCodes to work, so this is a huge set back for me. Please resolve this issue soon.