I presume that is because it is a complicated feature, but not technically impossible? Although perhaps using contentEditable* makes an implementation more difficult?
* From article: “CodeMirror would achieve that by leaning on native browser text editing (via contentEditable) rather than implementing text editing entirely in the library/javascript.”.
Edit: from https://blog.replit.com/codemirror “CodeMirror 6 is a complete rewrite of the CodeMirror editor with a focus on accessibility, touchscreen support, and extensibility.”. I expect that marjin really cares about accessibility. However, in my limited experience, as a lone developer I couldn’t make our complex product properly accessible unless that was the focus of say six months effort, which we couldn’t afford at the time.
* From article: “CodeMirror would achieve that by leaning on native browser text editing (via contentEditable) rather than implementing text editing entirely in the library/javascript.”.
Edit: from https://blog.replit.com/codemirror “CodeMirror 6 is a complete rewrite of the CodeMirror editor with a focus on accessibility, touchscreen support, and extensibility.”. I expect that marjin really cares about accessibility. However, in my limited experience, as a lone developer I couldn’t make our complex product properly accessible unless that was the focus of say six months effort, which we couldn’t afford at the time.