I'm trying to enable wpml translation management plugin and then it doesnt allow me to navigate to backend wp pages, it loads very slow and ultimately shows 504 Gateway timeout issue.
I checked in forums and someone suggested to put debug.log information, I did the same and here is the info
"[01-Jun-2019 17:13:49 UTC] PHP Notice: ob_end_flush(): failed to send buffer of zlib output compression (1) in /var/www/wp-includes/functions.php on line 4339
[01-Jun-2019 17:13:49 UTC] PHP Notice: ob_end_flush(): failed to send buffer of zlib output compression (1) in /var/www/wp-includes/functions.php on line 4339
"