Half footlets

Do you always have fun with slippers that slide forever? The manufacturers come up with some anti-slip measures, but they never really work for me. Sooner or later, the heel always slips around in the shoe. A few years ago, however, I bought a completely different variant of footlets. The heel is simply missing, so it cannot slide. Since then, I haven't seen these "half footlets" anywhere. But why does a woman have a sewing machine, right? ;)

Here is the pattern, and the blog has instructions on how to do it.