A 11spd shifter will move your 10spd mech correctly (but the right amount for a 11spd cassette), so you'll need a 11spd cassette too as well as the shifter. Mech is fine.
This is actually what I thought.
Actually, I'm wrong! ignore me.
@Chalfie started
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A 11spd shifter will move your 10spd mech correctly (but the right amount for a 11spd cassette), so you'll need a 11spd cassette too as well as the shifter. Mech is fine.