@ZellusYou can do this for single links by (in Firefox, other browsers should have something similar):
Right click link & select 'Copy Link Location'
Click [history] on browser menu, then 'Show All History'
Paste the link just copied into the [Search History] box of the newly opened 'Library' dialog, this should reduce the history list to just that link.
Right-click and click on 'Delete Page'
Refresh the browser page with the miscoloured link
I use this a lot to mark a previously read story as unread so I can easiy see which chapter I'm up to: replace the 'Delete Page' line above with:
Edit the [Search History] box to get all and only the links you want to forget (I'll use storiesonline.net/s/< story ID I want to forget >)
Type Ctrl-A to select all displayed links
Right-click on the highlighted lines and click on 'Delete Pages'
Refresh relevant pages (the story index and/or story info)