We recently decided to switch to quaternions for all the object in our scene in order to make it work with the gizmo. But we still use Euler angle as inputs, so we use the classic function RotationYawPitchRoll in order to go from Euler angles to quaternion and we observe that we don’t have always the same result using that function.
Here is a playground: Babylon.js Playground
You can see we have two cloned mesh and we only use RotationYawPitchRoll on one of them but the rotation is not the same.
I am sorry I am still not an expert in quaternions despite all my experience using it!
Thanks for your help guys