Some very important things are missing

I don’t have plans to add validation or minification at this time, since both would involve external libraries and would increase the size ( and slowdown ) the plugin.

as for adding syntax highlighting, there aren’t many available that will handle highlighting during data entry, but I am looking at two now for possible inclusion. the majority are only for static data.

Thank you for your reply!

Validation and minification would only triggered, when somebody saves the css. It doesn’t matter that the saving takes 1 second or 1,5 second because of the external libraries.

It is more important to have a valid css and to be minified, because it will improve the site and makes the site faster, not the admin.

Of course we are talking about few milliseconds.

Syntax highlighting can be implemented easily with ACE editor: https://ace.c9.io/

Meanwhile I have found Redux Framework, which have custom css module and it is using validation and syntax highlighting.

One thing I realized: there was already syntax highlighting in the plugin when you left your initial comment. It’s using CodeMirror. (ACE Editor is overkill for this project)

I’m actually adding some basic minification now, and looking at CSSTidy for the rest

to follow up: CSSTidy isn’t consistent in how it handles certain CSS variables, especially CSS3. So I’ll be adding minification on a basic level, but not much more at this time.