The css that problem : plugins/cms/resources/css/content/ContentToolEditor.css

/* ------------- LINK ------------- */
.mceContentBody a.simple,
.mceContentBody a.simple:hover,
.mceContentBody a.simple:link,
.mceContentBody a.simple:visited,
.mceContentBody a.simple:active

{ color: #006BB1 !important; text-decoration: none; }