Release note update

editions/prerelease/tiddlers/Release 5.1.16.tid

@@ -7,7 +7,44 @@ type: text/vnd.tiddlywiki
 
 //[[See GitHub for detailed change history of this release|https://github.com/Jermolene/TiddlyWiki5/compare/v5.1.15...v5.1.16]]//
 
-!! New and Improved Plugins
+!! Improved ~CodeMirror Plugins
+
+The ~CodeMirror plugin has undergone a substantial rewrite, with many new improvements:
+
+* Upgrade to ~CodeMirror version v5.36.0
+* Now modularised into:
+** Base plugin
+*** Basic lightweight configuration, approximately 240KB
+** Add-on plugins
+*** Search and Replace
+*** Auto-completion
+*** Fullscreen editing
+*** Auto-close brackets
+*** Auto-close tags
+*** SublimeText keymap
+*** Emacs keymap
+*** Vim keymap
+*** Highlighting modes:
+**** Javascript
+**** Xml
+**** Html (htmlmixed)
+**** Html (htmlembedded)
+**** Css
+**** Markdown
+**** X-Tiddlywiki
+* Automatic configuration (the configuration tiddler is not needed anymore)
+*** ~CodeMirror (engine.js) builds the configuration using information within the installed c~CodeMirror plugins
+* New control panel configuration tab:
+** Line numbers
+** Theme
+*** Editor font family (same as native TiddlyWiki)
+*** Cursor settings
+*** Line wrapping
+** Active line highlighting
+*** Autocompletion on/off (if installed)
+** Keymap
+
+!! Other New and Improved Plugins
 
 * New [[Dynaview Plugin]] makes it possible to build user interfaces that dynamically respond to changes in scrolling or zooming
 * Improved [[Text-Slicer Plugin|Text-Slicer Edition]] with customisable JSON rules
@@ -45,6 +82,7 @@ Prompted by the [[General Data Protection Regulation (GDPR)|https://en.wikipedia
 * [[Added|https://github.com/Jermolene/TiddlyWiki5/commit/c0569849d22f99623423d349c0d96ecae11ffbe8]] "rotate left" button to bitmap editor toolbar
 * [[Improved|https://github.com/Jermolene/TiddlyWiki5/pull/3180]] criteria under which certain editor toolbar buttons are displayed
 * [[Added|https://github.com/Jermolene/TiddlyWiki5/pull/3190]] support for a minimum length for the new tag field before the dropdown is shown
+* [[Improved|https://github.com/Jermolene/TiddlyWiki5/commit/02529a51d0be47477e62cd52dd5e4989a4993663]] consistency and reusability of the palette, language and theme switchers
 
 !! Hackability Improvements