Why does the Answer Source View no longer color code HTML?
Answers, Workspaces, HTML Answer Editor
Oracle Service Cloud, 18A, 18B, 18C, 18D
In the Oracle Service Cloud release 18A, the Answer Editor has been changed to be compatible with the Browser User Interface (BUI). Any feature in the previous Answer Editor that is not native to this new tool, may be added in a plug-in for a future release. This means that some of the old features will no longer be available. As an example, the 'Undo' option in the Source View of the Answer Editor is now grayed out and not usable. Another example is the HTML color coding (highlight) or line numbering in the Source View of the Answer Editor is no longer available.
There is no way to 'enable' these features for the Source View until the plug-in is written specifically for the Source View in the Oracle Service Cloud product. The Browser User Interface can be used to benefit from some of these features which are already included in the Answer Editor. The Source View color coding has now been added to the Oracle Service Cloud release 19A.
For more information see Answer 10205: Answer Editor Features.