You’ll want a 12-speed cassette. In a pinch you can run an 11-speed cassette as long as you’re in Erg mode and pick a gear that keeps your chain straight from front to back. The concern comes to mismatched chain and cassette / gear widths. Really recommend a 12-speed, though. For me, I also matched the exact tooth-count for each gear, too, so that in Standard or Resistance mode the shifting is identical inside and outside.
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