More info related to the change: https://hg.mozilla.org/mozilla-central/rev/5079bb7577182734823d6e4a3c468115d45a9dd9

--- a/browser/components/search/extensions/ddg/manifest.json	2023-04-06 23:48:16.983734806 -0600
+++ b/browser/components/search/extensions/ddg/manifest.json	2023-04-06 23:54:27.848103496 -0600
@@ -21,7 +21,7 @@
       "name": "DuckDuckGo",
       "search_url": "https://duckduckgo.com/",
       "search_form": "https://duckduckgo.com/",
-      "search_url_get_params": "t=ffab&q={searchTerms}",
+      "search_url_get_params": "q={searchTerms}",
       "suggest_url": "https://ac.duckduckgo.com/ac/",
       "suggest_url_get_params": "q={searchTerms}&type=list"
     }
--- a/browser/components/search/extensions/ddg-html/manifest.json	2023-04-06 23:48:16.987734810 -0600
+++ b/browser/components/search/extensions/ddg-html/manifest.json	2023-04-06 23:55:19.080158907 -0600
@@ -21,7 +21,7 @@
       "name": "DuckDuckGo (HTML)",
       "search_url": "https://html.duckduckgo.com/html/",
       "search_form": "https://html.duckduckgo.com/html/",
-      "search_url_get_params": "t=ffab&q={searchTerms}",
+      "search_url_get_params": "q={searchTerms}",
       "suggest_url": "https://ac.duckduckgo.com/ac/",
       "suggest_url_get_params": "q={searchTerms}&type=list"
     }
