Updated JavaScript in EGroupware apps (markdown)

JavaScript-in-EGroupware-apps.md

@@ -10,6 +10,10 @@ Our developer-install update script ```./install-cli.php``` runs the following c
 - ```grunt``` ---- " ----
 - ```npm run build``` running new ```rollup -c```
 
+> Our current [rollup.config.js](https://github.com/EGroupware/egroupware/blob/master/rollup.config.js) requires Node version 14! For Ubuntu you can [install Node 14.x following this instructions](https://github.com/nodesource/distributions#debmanual).
+
+> For development, specially debugging JavaScript, you probably want to [switch minifying off in rollup.config.js](https://github.com/EGroupware/egroupware/blob/master/rollup.config.js#L25), otherwise you are not able to set breakpoints on some lines.
+
 > Use ```npm run build:watch``` or click on the green run icon in package.json opened in PHPStorm to automatic build changed files for developing.
 
 #### Please note the following about ES6 modules: