Also thanks to @Calamity for testing and encouraging me.

And finally . . . apologies for taking so long to give it a try . . . I move at glacial speed these days . . .

UPDATE: Confirmed! The DDG icon has been banished from about:blank in Firefox!!

/me does a happy dance . . .

@HardSun . . . Thanks for taking the time to respond. The tab is not the problem it is the ddg icon which precedes it that I find annoying. Why can't I just choose whichever search engine I want at that time! I think the point is to box us all into patterns that will move us further down the chute to the abattoir . . .

Are you talking about the search bar icon to the left that has a drop down menu of other search engines? Provided you have other search engine shortcuts?

I think you might be talking about the about:config setting as per below, try setting it to false and see if that is it?

browser.urlbar.scotchBonnet.enableOverride

Otherwise please upload an image as tux_99 mentions.

below that you have the Address Bar settings: unselect Search Engines

If that doesn't solve your issue then maybe post a screenshot as it's not clear what exactly you are referring to.

@fsmithred . . . There was a time when I experimented a lot with about:config customization. That was then . . .

An about-blank page has always had "about:blank" in the urlbar until the last update after Chimaera moved to old,old stable and DDG decided to appropriate that "empty" space. I don't understand why there even has to be a default search engine. I have removed all the other search engines I use from the list. I'm not that happy with any of them

@HardSun . . . Thanks for taking the time to respond. The tab is not the problem it is the ddg icon which precedes it that I find annoying. Why can't I just choose whichever search engine I want at that time! I think the point is to box us all into patterns that will move us further down the chute to the abattoir . . .

/me longs for the idylic pre-digital days . . .

1) go to about:config
2) copy paste this into the search browser.startup.homepage
3) double click that link and change whatever is there (usually its about:home) to chrome://browser/content/blanktab.html

I cant help with the duckduckgo icon thing sorry.
arkenfox user.js link if you are interested.
https://github.com/arkenfox/user.js/

In case the search bar gets disabled by an update, here's how to get it back.

https://support.mozilla.org/en-US/questions/1356391

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future. Since I use this one myself, I feel comfortable mentioning it, even if it does turn out to be temporary relief only.

(2) In the search box in the page, type or paste handoff and pause while the list is filtered

(3) Double-click the browser.newtabpage.activity-stream.improvesearch.handoffToAwesomebar preference to switch the value from true to false

Edit: I tried it. "about:blank" gives me a blank page. In the address bar, it says something like "Search with ddg or enter a url" but there's no icon and the page is blank. It is still possible to search in the address bar but it doesn't jump there from the search bar.

Edit2: Sorry, I forgot I was in Chimaera when I did the test. In excalibur there's a duck icon in the address bar. I assume that can be changed by changing the default search engine, in case you like the bing or wikipedia icon better. Do what I do and don't look at the duck.

Note that chromium and palemoon still respects about:blank.

Is there any way I can get FF to go back to opening a blank page without that stupid DDG icon when it is told to do so?

Everybody should have such catastrophic problems . . . LOL!