>From the wget manual (at https://www.gnu.org/software/wget/manual/wget.html#Time_002dStamping): "If the local file does not exist, or the sizes of the files do not match, Wget will download the remote file no matter what the time-stamps say." However, using Wget 1.20.3 it only downloads the remote file when the sizes do not match if we're using "--no-if-modified-since", otherwise it doesn't do it. As I've seen Wget 1.16 follows the behavior described on the manual (that version doesn't have "--no-if-modified-since").
If I'm right I suppose the manual should be updated
