In page 110 of the RISC-V Specifications the format for the pseudo-instruction jr is jr rs.

When I used jr ra in RARS I got the following error:
Too few or incorrectly formatted operands. Expected: jr t0, -100

I think keeping the format jr t0, -100 would be beneficial but also supporting the official one is important.

Where does RARS handle pseudo-instruction in the source code?