if you enable a bunch of unsafe options they can do some of them, but they tend to err on the safe side when it comes to native built-in methods like these on D

if you enable a bunch of unsafe options they can do some of them, but they tend to err on the safe side when it comes to native built-in methods like these on Date objects. also, some minifiers optimize for gzip size where the effect is not as drastic, but the browser still has to parse the un-gzipped source afterwards. it depends on the weighted costs built into each minifier.