Anchor hyperlinks inserted in a Rich Text field might be rendered with the wrong href attribute value. For example, the expected:
<a href="#">Text</a>
<a href="#&">Text</a>
<a href="# ">Text</a>
are rendered as:
<a href="##">Text</a>
<a href="#&#">Text</a>
<a href="# ##">Text</a>
To resolve the issue, consider one of the following options:
Alternatively, you can comment out the below processor found in the Sitecore.config file:
<processor type="Sitecore.Pipelines.RenderField.SetAnchorsPositionInLinks, Sitecore.Kernel" />