> .. in favor of targeted JS libraries that extend HTML capabilities.
Do you mean libraries like Turbolinks[1] and/or Intercooler[2] here? I'm interested in what libraries you use, and others like these which help "bridge the gap" between traditional and single-page sites.
Yes, those are some of the examples. You can roll your own as well. With modern JS and CSS selectors you can create useful, reusable libraries with just several dozen lines of straightforward code.
Unpoly [1] is another one in that camp. Made good experiences with to smoothen page transitions in a server-side rendered app [2]. I find this model much more approachable for backend devs than going all-in on SPA. It doesn't help of course with more fine-grained interactions like say in-place editing in a table.