Mobs try (and succeed) to jump closed fence gates.

Animals and mobs are managing to climb over fence gates from Extra Trees. This can possibly be solved by setting the method 'getBlocksMovement()' in the class 'binnie.extratrees.block.decor.BlockGate' to always return false.

Note: Vanilla mob AI has specific checks for vanilla gates and won't support modded versions. This specific check can be found at 'net.minecraft.pathfinding.PathFinder' line 339