I brushed up the lit-html sample to run with the latest version of the library I also found this article on TLA+ that has a detailed discussion on temporal formulas (p405)
I am still parsing the article, so I don't have much comment
This article on PWA vs native apps is certainly worth your time. Not fundamentally new arguments, but it's put in a very detailed and coherent way. Looks like Starbucks has created the gold standard of PWAs.