sltiu note incorrect? (RV32I Base Integer Instructions)

[MarkGFaust]

Is this note correct? I believe the immediate field is sign extended (not zero extended) and then is treated (along with rs1) as an unsigned value for the comparison.

See RISC-V Instruction Set Manual, Volume I: Unprivileged ISA, December 13, 2019. Page 18:

"SLTI (set less than immediate) places the value 1 in register rd if register rs1 is less than the sign extended immediate when both are treated as signed numbers, else 0 is written to rd. SLTIU is
similar but compares the values as unsigned numbers (i.e., the immediate is first sign-extended to
XLEN bits then treated as an unsigned number)."