Inserting an URL through source code with CSS properties and clicking on Insert/Edit on the link will override the CSS properties and bring the URL to the default configuration.
Click in the Text field and click the <gt; toolbar icon to display the aource code.
Insert the following text:
<a href="https://www.servicenow.com" title="https://www.servicenow.com"><span style="color: #090;">https://www.servicenow.com</span></a>.
Click the OK button.
Select the URL, click the Insert/Edit link, and click OK
Note that the color is not applied and the source code shows as:
<p><a title="https://www.servicenow.com" href="https://www.servicenow.com">https://www.servicenow.com</a></p>
After carefully considering the severity and frequency of the issue, and risk of attempting a fix, it has been decided not to address this issue. We do not make this decision lightly, and we apologize for any inconvenience. If you have any questions regarding this problem, contact ServiceNow Customer Support.