This update isn't a large update game wise, however it does extend the reach of the plugin by adding in support from 1.15 all the way back to 1.12!
So if you have been running 1.15 just for this plugin you could now go back to 1.12 if you really wanted to! There will not be support before 1.12 because the games code back then was not very good and bad coding practices were used which would require entirely new code to be written just to work with dieing version and unsupported by Mojang themselves so be happy to have some backwards compatibility! In the future i will always support up to 4 versions backwards! So when 1.16 comes out, i will support from 1.12 to 1.16, but after that i will drop the last version in new version of M&H so you could use dated versions of M&H but you would miss out on some content.
All in all im sure this will help a lot of users!