Spigotmc: https://www.spigotmc.org/resources/jfixlectern-fix-crash-server-with-lectern.101189/
Support Version: +1.14.4
Not required for version 1.13 or older because Lectern is not available.
Also not required for version 1.18 and above!
If you have Anti-Exploit plugin, you do not need this Because this problem is old and must have been fixed by these plugins.
For example :
[2LS] ExploitFixer