Skills granted by Forbidden Flesh & Flame are unassigned of the left mouse button on zone change

Skills granted by Forbidden Flesh & Flame are unassigned of the left mouse button on zone change.

Scenario:
The Skill bone armour can be granted by the jewels Forbidden Flame & Flesh with the ascendancy notable "Bone Barrier".

The skill is then assigned to the left mouse button as shown in the image below.

When changing a zone (tested with hideout to any map) the skill gets unassigned from the mouse button left and the "attack" skill is assigned to it.

This seems to be unintentional and forces the player to re-assign the spell on every zone change.

Before changing zone:

After changing zone: