If you become a Mudcat member, you get your own personal page where you can keep track of any threads you want to follow up. When you click on "add to tracer", the link to that particular thread is added on to your personal page, & stays there until you take it away with "delete from tracer".
Membership has other advantages too, like access to the Mudcat Chat room, & the ability to send private messages to other members. And (at least for now) it's all free!
Click on the title "The Mudcat Cafe" & explore from there, for more details about how to use the Digital Tradition Lyrics database, the Search Facility, the Forum Search, etc. etc.