Patch status: fixed in >=qtwebengine-6.11.3 (incl. 6.140.0)

https://bugs.gentoo.org/984271
https://qt-project.atlassian.net/browse/QTBUG-149946
https://codereview.qt-project.org/c/qt/qtwebengine-chromium/+/768932
--- a/src/3rdparty/chromium/third_party/blink/renderer/platform/wtf/text/text_codec_icu.cc
+++ b/src/3rdparty/chromium/third_party/blink/renderer/platform/wtf/text/text_codec_icu.cc
@@ -167,5 +167,5 @@
     }
 
-    registrar(standard_name, canonical_name.Ascii().c_str());
+    registrar(standard_name, standard_name);
 
     UErrorCode error = U_ZERO_ERROR;
@@ -179,5 +179,5 @@
         DCHECK(U_SUCCESS(error));
         if (U_SUCCESS(error) && alias != standard_name && IncludeAlias(alias)) {
-          registrar(alias, canonical_name.Ascii().c_str());
+          registrar(alias, standard_name);
         }
       }