One of the useful plugins is an extension called Marco’s noFollow. It is intended to set attributes for external links with your project.
noFollow


So, Marco’s noFollow plugin that allows you to set the attributes:
Attribute “rel”
Setting “no follow”, if not specified in the “rel” attributes previously, unless specifically rel = “follow”.
Enhanced installation of the tags “no follow”.
The division of attribute “no follow” to remove “nofollow”.
The option “No change” to stop the change tags.
The attribute “target”
Open link in new window (_blank), unless otherwise predetermined, and the goal is not specified.
Open link in new window (_blank) – the attribute is assigned a value (_blank).
To open in the parent/child window (_parent), the attribute is set to (_parent).
CSS management
“Everything except” – rewrites all tags “a href”, except those prescribed in css classes.
“No one, except” – does not overwrite any of the tags “a href”, except those prescribed in css classes.
“CSS classes” feature that allows you to split a comma certain classes for tag “nofollow”.
This extension is unique in its kind, as it allows you to change the fine settings of external links and their attributes.

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