The implementation of your feature request is a very complex task, because there could be multiple different and nested elements in the selection and you should handle different scenarios. If you test the FontSize dropdown which is based on the browser's FontSize execCommand
command, you will reproduce the same behavior, e.g. only the contents of the <li> tags is changed, without the numbers.
If you would like to achieve your requirements, you should implement your own solution based on text ranges. You can create a text Range in RadEditor's content area using the following code:
var currentRange = editor.getSelection().getRange();
After that inspect the selection, get reference to the <li> tags and modify them.
You can find additional information about the ranges in these articles:
Note that this is a custom functionality, which is not offered by RadEditor out-of-the box and we do not support it.
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