Thanks for your thoughtful reply; I appreciate your analysis. Here are a few more facts to aid your analysis process:
Malwarebytes stopped the redirect, but it was the download that triggered the attempted connection to deloplen. That's why I raise this concern here. No connection to deloplen was actually made.
If something were already on my PC, would I not have seen this attempted redirect before now? Which, of course, I have not. Nothing before, nothing since, and I expect that I would have seen that if my PC were already infected. I presently have none of these symptoms of a deloplen infection:
popups and newtab pages are loaded without your request
when you go to a webpage, you’re often redirected to another web-site that you do not intend to visit
your personal computer starts automatically installing unexpected software
unwanted icons on your desktop
your browser home page has modified and you are unable to modify it back
you cannot update your antivirus software
slow Internet browsing speeds
your web-browser crashes
A full scan, by both Malwarebytes and Windows Defender shows nothing amiss.