Editor indentation for Emacs and Sublime Text; container guides point to editor support (from dev 5d35f256476e)

doc/install/macos_container_install.md

@@ -124,10 +124,12 @@ That's it — you're running Klammertext.
   together, and run `ktext` from that folder.
 - **Runs natively.** On Apple Silicon, `container` runs the native arm64 image
   with no Rosetta translation.
-- **Fonts.** The default fonts (Crimson Pro, Open Sans, Inconsolata) are built
-  in, so PDFs work with no internet connection. If you ask for a different font
-  by name, Klammertext downloads it from Google Fonts the first time, which
-  needs an internet connection.
+- **Fonts.** The default fonts (Crimson Pro, Open Sans, Inconsolata, and
+  others) are built in, so PDFs work with no internet connection. Font
+  resolution is entirely offline: asking for a font that isn't installed
+  lists the available fonts, and additional fonts are installed from font
+  files you already have with `kdesc --font install <folder>` (`kdesc --font
+  help` explains).
 - **Updating later.** When a new version is announced, run `klammertext-update`
   in Terminal.
 - **If you also build Klammertext from source on this Mac.** Most people don't —
@@ -143,6 +145,20 @@ That's it — you're running Klammertext.
   run `container system stop`; start it again with `container system start` next
   time.
 
+## Editor support (Emacs, Sublime Text)
+
+Editing Klammertext is nicer with editor support: syntax highlighting,
+delimiter matching, and indentation for Emacs and Sublime Text. It is not
+inside the container image — it belongs on your Mac, next to your editor.
+Download it from either place:
+
+- <https://andykopra.com/Klammertext_editing.zip> — unpacks to `emacs/` and
+  `sublime/` folders
+- the Klammertext source repository,
+  <https://git.andykopra.com/ack/klammertext>, directory `doc/edit/`
+
+Each package's README explains its installation.
+
 ## If something goes wrong
 
 - **`command not found: ktext`** — you didn't open a new Terminal window after