This resource is still updated and developed, though no significant feature requests will be added to it for the moment. (Written on 05/01/2019)
Made by request of @CollinPotato, this will remove all blocks of a certain (configurable) ID when the chunk is loaded.
I made this because too many of certain blocks can cause lag or even crashes. For example, if you have too many tile entities in your world, I would give you a link to this plugin and tell you to remove Hoppers or Chests, etc.
Note: You must load the chunks for the blocks in them to be checked! To load them, just walk (or teleport) to the chunks' location!
Configuration has got two values, "ID" and "Above". "ID" is the IDs of the blocks you want to remove, "Above" means that any blocks at the same height or below it do not get removed.
By default it will remove snow.
As of update 1.3, you can list multiple blocks to be removed, like so: