Microsoft replaced RCtrl with a Copilot key on new laptops. The firmware sends LeftMeta+LeftShift+F23 as a burst of taps, so standard remapping doesn't work.
The fix uses keyd (https://github.com/rvaiya/keyd). Put this in /etc/keyd/default.conf:
[ids]
*
[main]
leftmeta+leftshift = overload(control, noop)