I'm forever looking out for the best Markdown processor, and I just happened to cross paths with HastyScribe (https://h3rald.com/hastyscribe/) a multi-platform single file command line executable who seems to be able to create valid self-contained (embedding images, for example) HTML5 pages.
HastyScribe has a very easy and straightforward user guide online at https://h3rald.com/hastyscribe/HastyScr ... rGuide.htm and is based on Discount (another previously unbeknownst converter written in pure C; see https://www.pell.portland.or.us/~orc/Code/discount/). Anyone still wondering about its differences to the tools mentioned above can have a look at https://github.com/h3rald/hastyscribe#w ... converters.