snipershady wrote: ↑
Thu Jan 16, 2020 8:50 am
0 log error from that call
So long as we're talking about the PHP error log (and not the phpBB Errors log in ACP, or some other error log that doesn't receive specifically the PHP errors) then I guess that rules that out too.
The additional tests like disabling mod_security certainly sound reasonable, and if we're "lucky" maybe it is some mod_security rule engaging against the way phpBB 3.3.0 presented some fields differently. Note if "it's mod_security" is true, one might also expect that the web server error log (in this case, still not phpBB's logs, and not necessarily the same log PHP errors log to) would be receiving details about the mod_security rule which has blocked the inbound request from being processed.
For myself, the point I would also be at now is to take a LAN trace of my communication to the phpBB server using Wireshark, in order to see what was actually wrong and/or what additional clues or text may be present in the HTTP response from the server which couldn't be decoded, and for which the web browser declares "content encoding error."
That's "trickier" if you have HTTPS enabled, since the communication is encrypted and you have to get your web browser to share key information with Wireshark in order to decrypt what you've captured. I'm certainly willing to do it for you, but since demonstrating the issue requires an administrator account for your board, so I'm sure you would prefer to handle it yourself if possible.