how to save plot with `file` para with a `tpar` multiplot

# plot layout
tpar(mfrow=c(2,1))

tinyplot(X_new, mean_coverage_rate, 
         xlab="local test point", ylab="coverage rate",
         ylim=c(0, 1.0),
         col="forestgreen",
         draw=abline(h=1-alpha, col="orangered", lwd=1.2),
         main="Local coverage with kernel estimation", sub="estimator")


tinyplot(X_new, beta_hat*X_new, 
         xlab="local test point", ylab="prediction interval",
         col="forestgreen", 
         sub="Coverage in one trial",
         draw={
           segments(x0=X_new, y0=beta_hat*X_new-half_interval[, 1],
                    x1=X_new, y1=beta_hat*X_new+half_interval[, 1],
                    lwd=2, col="forestgreen")
           points(X_new, X_new+rnorm(40, sd=0.1), pch=17, col="gold1")
         },
        file="/Users/desktop/a.jpg"
         )

hi, I'm wondering how to save plot with file para with such a tpar layout above, it seems that tinyplot always save a png for the 2nd plot seperately...

Reproduce the supplied R script using tpar(mfrow=c(2,1)), two tinyplot calls, and the file argument. Start at tinyplot's file-handling entry point and determine how it interacts with the tpar layout. Done means the two-panel plot is saved as one requested image, or the supported limitation is clearly documented.