Hello Max,

let me make a last remark about the pushFrame before you release it. Your code works fine and I can't figure out any problems:-)
(little changes: clamp frame.zaxis.x to [-1;1] | ?90:-90; -> Math.PI/4;-Math.PI/4)
The function sets in gimbal lock ry to ?90:-90. Am I right, that we need in that situation at least a rx- or rz-calculation?
Something like (not tested):
rz = Math.atan2(frame.yaxis.z,frame.yaxis.y); or a direction dependent rz=Math.asin(frame.xaxis.y)??? with rx=0
As mentioned, in tests I didn't run in that situation:-)

Have a nice day
Karsten