Have been using this Unsplash POTD for several days and found the wallpaper doesn't change by day.
Then I found two problem in the code:
1. The HTML page contains a banner image, which almost never change. It is fetched first with previous regular expression.
2. The photos on the page doesn't update everyday. Sometimes they update a bunch of photos at one time.
So I changed it to global match and pick a random one from latest photos. Looks more like picture of the day.