Lighting bug with inventory, boat and hand

Hello!

My problem is that when I open the inventory and move the mouse inside the inventory frame, the color of the boat becomes darker than before. However, if I move the mouse outside of the inventory frame, the color of the boat becomes light again.

This problem also occurs with my character's hand. As the boat gets darker, my character's hand gets darker as well.

What could cause this problem? Thank you in advance for your reply. I wish you a wonderful day!

Oh by the way I am usin ubuntu (gnome) version 19.10