When in spectator mode, the game will randomly let you try to break blocks. It will momentarily show a particle as if the block is breaking, but then it will not let you even try to break anymore.

Steps to reproduce:

1. Break a block completely in survival mode.
2. Switch to Spectator mode.
3. Try to break a different block. You may see particles. It is more consistent than interacting with a tileEntity, which can also be used to reproduce it, but very inconsistently.

Other method (very rarely works):

1. Interact with a tileEntity in Survival mode.
2. Switch to Spectator mode.
3. Interact with the same tileEntity
4. Try to break a block. You very rarely will see particles.

This relates to MC-46766 and MC-55233.