Test tdot accent and accent=false on mstyle, mover, mo.
<math xmlns="http://www.w3.org/1998/Math/MathML"> <mstyle mathsize="200%" displaystyle="false"> <mover> <mi>x</mi> <mo> ⃛</mo> </mover> <mo> ≠</mo> <mstyle accent="false"> <mover> <mi>x</mi> <mo> ⃛</mo> </mover> </mstyle> <mo> =</mo> <mover accent="false"> <mi>x</mi> <mo> ⃛</mo> </mover> <mo> =</mo> <mover> <mi>x</mi> <mo accent="false"> ⃛</mo> </mover> </mstyle> </math>