Composer Editor Rel Attribute

Hello,
Trying out the Composer editor and was wondering if there's a way to not add a rel attribute to links and/or a "nofollow" value? It appears when adding a link, rel="alternate" gets added by default. Seems like there should be something like a "none" or "other" option, however the only way to remove/edit a rel attribute is by manually editing the source code.

Thanks in advance for your assistance.