Players get random mining fatigue

[skerit]

I made a new issue for this because issue #156 states that only happens when switching from a modded item.

There currently are no modded mining tools on my server, so that can't be it.
There has always been an occasional mention of this in the past, it's only now that we started a new map (and have a lot of players at the same time) that it's getting more frequent.

I tested a few things:

• Mining a modded block & switching out the item just before it breaks
• Mining a modded block & moving away just before it breaks

But those don't seem to trigger it.
Relogging removes it.

[TheEpicBlock]

I know there are issues with blocks that can be broken immediately. Could also be related to #34