Player model inside of inventory is unusual

The player model inside of the inventory menu is not behaving the way it should. When moving the cursor below the head of the model, the legs begin to crunch towards the center of the model. This is not the correct behavior, the legs shall stay relatively straight when the head is following the cursor.

• Steps to reproduce -
• 1 - Enter the inventory menu (Preferably in survival mode, for ease of access)
• 2 - Move the cursor around the screen. Observe the head of the player model following the cursor, and the legs of the model awkwardly crunching inwards.