I've provided some custom CSS for this before:
Hashtag feature or plugin
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Stumbled on this unique variation a little earlier and thought it even kind've loaded like something you'd see on NodeBB.
Wasn't sure what the devs here had thought about some sort've #hashtag functionality, but here's one idea.
http://hashtag.handypress.io/hashtag-wordpress-post-relative-links-demo/
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