DID example fails

[MatthieuStigler]

Trying to run the DID example fails, with error "non-conformable arguments"

Reproducible code:

library(MCPanel)
DID(matrix(c(1,2,3,4),2,2), matrix(c(1,1,1,0),2,2))
#> Error in t(M_control_rows) %*% W: non-conformable arguments

^{Created on 2021-08-17 by the reprex package (v2.0.1)}