The HTMLEditor is used on the Admin section of PowerStore 3, and specifically to update product description and update CMS content.
So you will have to decide if upgrading will improve those areas of PowerStore 3.
And if you decided to upgrade the upgrade process is straight forward, basically you will need to remove the HTMLEditor from the page and remove the include file at the top of the page and then insert a new HTMLEditor, but you have to make sure you use the same name and the same default value that the old htmleditor instance used.