In this snapshot, after 30 seconds to 1 minute of playing, any of the following happen:

• Blocks cannot be placed from inventory when right-clicking on other blocks
• Blocks cannot be mined
• Boats cannot be entered
• Boats cannot be hit
• Chests cannot be opened
• Probably other similar ones not tested (cannot use or hit minecarts, trap chests, etc.)
• Mobs and item entities are not affected (i.e. can pick up and drop items, hit Drowned)

This has only happened on this snapshot. Saving and quitting to menu and reopening a world fixes the issue but it presents again after a minute or less. Restarting computer or launcher does not change this either.

UPDATE:

In 1.16 pre-1, same issues present.

In 1.16 pre-2, these issues no longer present, and now the issue is with mobs and item entities instead. I cannot hit mobs, and one of two item entities in my inventory disappeared upon death while the other did not (gamerule keepInventory not enabled).

This is in survival mode, seed used '4'.