The MechJeb2 gui spawns at left upper corner making it unable to use it due to gui of selected thing appears at zone where only its right bottom corner is visible, but when you try to move it, it teleports back to its plac

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Found out that you can move the mechjeb gui in vab or sph, i pressed on settings and it moved to another location which is better to me, do the same when you have the same issue