@test: The PR now applies but with some issues:

D:\wamp\www\joomla-cms>curl https://github.com/joomla/joomla-cms/pull/3833.diff | git apply
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 2972k 100 2972k 0 0 1441k 0 0:00:02 0:00:02 --:--:-- 1546k
:37062: trailing whitespace.

:37166: trailing whitespace.
*
:37176: trailing whitespace.

• Collection classes mixing in this trait provide a concrete :37181: trailing whitespace. * :37184: trailing whitespace. * warning: squelched 167 whitespace errors warning: 172 lines add whitespace errors.

I guess these are issues in the Codemirror files rather than Joomla! code.

Other than that all looks good for me. The Fira Mono font looks pretty nice too.

There are changes in files unrelated to Codemirror. So please remove syntax="html" and the other unrelated changes from the following files so this PR only affects files regarding codemirror itself.

• administrator/components/com_categories/models/forms/category.xml
• administrator/components/com_content/models/forms/article.xml
• administrator/components/com_templates/views/template/tmpl/default.php

I guess syntax="html" is not actually necessary since it's the default anyway.

The changes to administrator/components/com_templates/views/template/tmpl/default.php are related to CM though. A message about how to use CM is written in to the template file for some reason instead of being displayed by CM. We need to remove this message because CM will display it now.

Ah I see

The xml description string change is unecessary.
PLG_CODEMIRROR_XML_DESCRIPTION="This plugin loads the CodeMirror (v4.3) editor."

let's keep the former one:
PLG_CODEMIRROR_XML_DESCRIPTION="This plugin loads the CodeMirror editor."

The new version is stated in codemirror.xml.

I don't mind changing that back (it makes updates slightly less troublesome anyway) but then I wonder if we should display xml version information in more places. Now it's only displayed in the Extensions Manager but maybe displaying in the Plugin Manger would be useful. There's certainly enough room for another column in the list. I suppose that's a task for a different PR.

If we do that for plugins, then someone will ask to do it for modules where the manager is crowded. I guess we can live with the version being displayed in Extensions Manager=>Manage. :)

Looks like not many important changes in 4.4 but I don't want to fall behind so here it is.

Well, I hope it's pretty self-explanatory but, after applying the patch, you should modify the plugin options because they've changed a lot. You'll find many new options for the appearance of the editor, font choices, color schemes, etc. Then, use the editor to edit any kind of code, it should do proper syntax highlighting for html, css, javascript, php, etc.

Merged into 3.4-dev branch. Thanks!