Stuck in Nether Portal animation when switching to Spectator mode

Summary:
After entering the nether from overworld and then changing to spectator mode while staying in the portal makes the player get stuck in nether portal animation even after moving away from the portal while still in spectator mode.

Steps to reproduce:

1. Build and activate Nether portal.

2. Enter the portal and teleport.

3. Standing in the portal change the mode to the spectator.

4. Try to leave the portal.

Observed results:
The animation of the portal on the screen remains even when you left the portal.

Expected results:
When switching to the spectator mode, the animation of the portal should not be on the screen.

Video: