Empty block height decreases slightly when another block is added or deleted.

Prereq.: The blocks are empty, no configuration is added. No preview is generated.

Steps:
1. Create a new Landing Page.
2. Add a block to one of the drop zones.
3. Add another block and observe the height of the first block.
4. Keep repeating step 3 several times observing the height.
5. After a significant number of blocks has been added start deleting the blocks.
6. Observe block height.
Issue: Block height keeps decreasing slightly every time a block is added or deleted.