It's looking like I have to do some revamping of the blog template - seems like I already did this once, but perhaps that was for another blog, on some other plane of existence. I got the information from the blogger.com Help page titled What are Quick Edit Links? - understanding of this answer required that I know that I am using Classic Templates, but given that pre-existing knowledge, the answer given was quite helpful, thank-you very much.

I should now [I suppose] go through the exercise of running the output of my blogger template through the HTML and CSS Validators to find the various errors that are sure to exist under contemporary standards.