Update README.md

Reorganize some content, add more context/links, remove obsolete information, wrap lines.

README.md

@@ -2,7 +2,7 @@
 
 This is an attempt at providing a fully browser-based reStructuredText playground
 that anyone can use without setting up a server.
-Try it out (attention: very rough prototype!) at <https://waldyrious.github.io/rst-playground>.
+Try it out at <https://waldyrious.github.io/rst-playground>.
 
 ## Motivation
 
@@ -16,15 +16,34 @@ where I can try out the syntax and see how it renders.
 
 More detailed background:
 
-- [Though there are various implementations of rST parsers](https://stackoverflow.com/questions/2746692/restructuredtext-tool-support),
+- [Though there are various implementations of rST parsers](https://stackoverflow.com/q/2746692/266309),
   the reference/canonical one seems to be [docutils](https://docutils.sourceforge.io),
   which includes, among other modules, `rst2html` (converts from reStructuredText to HTML)
-- [There doesn't seem to be](https://stackoverflow.com/questions/16335197/are-there-any-restructuredtext-to-html-parseror-library-perhaps-written-in-j) any JavaScript-only implementation which could be used in fully client-side browser app
-- Existing browser-based playgrounds called back to a server-side renderer
-  - Note: "called" is in the past tense because [rst.ninjs.org](http://rst.ninjs.org) ([anru/rsted](https://github.com/anru/rsted)), and [livesphinx.herokuapp.com](https://livesphinx.herokuapp.com/) ([readthedocs/livesphinx](https://github.com/readthedocs/livesphinx)), a fork of the former, are both defunct as of Dec 2022
-- There is [seikichi.github.io/restructured](https://seikichi.github.io/restructured/) which does work fully in-browser, but it's incomplete and unmaintained
-- [rst-live-preview](https://github.com/frantic1048/rst-live-preview) is a Node.js CLI tool that [relies](https://github.com/frantic1048/rst-live-preview/blob/42fac86586469964c06dcd867db714e35d97a3ec/rst-loader.js#L17) on a Python CLI tool ([rst2html5](https://github.com/marianoguerra/rst2html5/) — attention, this is not docutil's `rst2html`, though see [this](https://github.com/marianoguerra/rst2html5/issues/20) and [this](https://github.com/marianoguerra/rst2html5/issues/87))
-- Since there doesn't seem to be a JavaScript rST renderer, perhaps [Pyodide](https://pyodide.org) could be used to run the Python-based `rst2html` directly the in the browser, using .
+- Existing browser-based playgrounds called back to a server-side renderer in Python, also relying on `docutils`
+  - Note: "called" is in the past tense because both
+    [rst.ninjs.org](http://rst.ninjs.org)
+    (source: [anru/rsted](https://github.com/anru/rsted)),
+    and [livesphinx.herokuapp.com](https://livesphinx.herokuapp.com/), a fork of the former,
+    (source: [readthedocs/livesphinx](https://github.com/readthedocs/livesphinx))
+    are defunct as of December 2022
+- [There doesn't seem to be](https://stackoverflow.com/q/16335197/266309)
+  any pure JavaScript implementation which could be used in a fully client-side browser app
+  - There is [seikichi.github.io/restructured](https://seikichi.github.io/restructured/),
+    which does work fully in-browser,
+    but it's [incomplete](https://github.com/seikichi/restructured/#progress)
+    and [unmaintained](https://github.com/seikichi/restructured/issues/15)
+  - [docutils-js](https://github.com/docutils-js/docutils-js) is an attempt to port `docutils` to JavaScript,
+    but it's also [incomplete](https://github.com/docutils-js/docutils-js#addendum),
+    and appears to be abandoned as well.
+  - [rst-live-preview](https://github.com/frantic1048/rst-live-preview) is written in JavaScript,
+    but it [relies](https://github.com/frantic1048/rst-live-preview/blob/42fac8658/rst-loader.js#L17)
+    on the Python CLI tool [rst2html5](https://github.com/marianoguerra/rst2html5/)
+    (attention, this is not `docutils`' `rst2html`,
+    though see [this](https://github.com/marianoguerra/rst2html5/issues/20)
+    and [this](https://github.com/marianoguerra/rst2html5/issues/87))
+    to do the actual conversion.
+- Given the lack of a pure-JavaScript rST renderer, perhaps [Pyodide](https://pyodide.org) could be used
+  to run the Python-based `rst2html` directly the in the browser.
 - Pyodide even has the relevant [packages](https://pyodide.org/en/0.19.1/usage/packages-in-pyodide.html)
   ([docutils](https://docutils.sourceforge.io) and [pygments](https://pygments.org)).
   See docs: [Loading packages](https://pyodide.org/en/0.19.1/usage/loading-packages.html#loading-packages).