Version 5.18.0 ### Bugfixes Make sure [gutter backgrounds](http://codemirror.net/doc/manual.html#addLineClass) stick to the rest of the gutter during horizontal scrolling. The contenteditable [`inputStyle`](http://codemirror.net/doc/manual.html#option_inputStyle) now properly supports pasting on pre-Edge IE versions. [javascript mode](http://codemirror.net/mode/javascript): Fix some small parsing bugs and improve TypeScript support. [matchbrackets addon](http://codemirror.net/doc/manual.html#addon_matchbrackets): Fix bug where active highlighting was left in editor when the addon was disabled. [match-highlighter addon](http://codemirror.net/doc/manual.html#addon_match-highlighter): Only start highlighting things when the editor gains focus. [javascript-hint addon](http://codemirror.net/doc/manual.html#addon_javascript-hint): Also complete non-enumerable properties. ### New features The [`addOverlay`](http://codemirror.net/doc/manual.html#addOverlay) method now supports a `priority` option to control the order in which overlays are applied. MIME types that end in `+json` now default to the JSON mode when the MIME itself is not defined. ### Breaking changes The mode formerly known as Jade was renamed to [Pug](http://codemirror.net/mode/pug). The [Python mode](http://codemirror.net/mode/python) now defaults to Python 3 (rather than 2) syntax.