How did you make that?!
Not yet, but it is a real screenshot of a working STKM+jetpack. Activated by passing through grav wall, shoots PLSM, left/right/up acceleration using the normal arrow keys, down key still spawns elements (and the PLSM does not change the current STKM spawn element), and STKM is immune to hot plasma while jetpack is enabled. STKM is still affected by gravity, so keep pressing up to hover.
Edit: https://github.com/jacksonmj/The-Powder-Toy/tree/tptpp-jetpack , STKM needs a graphical effect when jetpack is enabled though.