The spectator mode hotbar opens after switching to spectator mode if the middle mouse button was clicked while using an item

The Bug:

The spectator hotbar opens after switching to spectator mode if the middle mouse button was clicked while using an item.

The fix for MC-305544 throws away stray middle clicks, but only while no item is being used. A middle click made while holding up a shield, bow or spyglass is kept, and if the player then becomes a spectator, the spectator hotbar is opened.

Steps to Reproduce:

1. Switch to creative mode and hold a shield.

2. Hold the right mouse button to block and keep holding it.

3. Click the middle mouse button once.

4. Still holding the right mouse button, press F3 + N to switch to spectator mode.

5. Observe if the spectator hotbar menu is open.

Observed Behavior:

The spectator hotbar opens after a middle click made while using an item.

Expected Behavior:

The middle click would be disregarded, just like it is when no item is used.