While we are still on the Bees and Bugs update I thought I'd bug test the other Bugs of MC and found that Silverfish and Endermites react weirdly when around slabs.

Here are the steps to replicate the Bug.

Step 1 place slabs in one of the configurations shown below

Step 2 Summon a Silverfish

Step 3 Get to the other side of the enclosure and Punch the silverfish

Now the silverfish will notice you but won't approach or attack you unless it gets somehow pushed under the fence.