eget: add support for utf-8 filename in Content-disposition

bin/tools_eget

@@ -1027,10 +1027,11 @@ url_get_filename()
     ! is_httpurl "$URL" && basename "$URL" && return
 
     # See https://www.cpcwood.com/blog/5-aws-s3-utf-8-content-disposition
+    # https://www.rfc-editor.org/rfc/rfc6266
     local cd="$(url_get_header "$URL" "Content-Disposition")"
-    if echo "$cd" | grep -q "filename\*=UTF-8" ; then
+    if echo "$cd" | grep -qi "filename\*=UTF-8" ; then
         #Content-Disposition: attachment; filename="unityhub-amd64-3.3.0.deb"; filename*=UTF-8''"unityhub-amd64-3.3.0.deb"
-        echo "$cd" | sed -e "s|.*filename\*=UTF-8''||" -e 's|^"||' -e 's|";$||' -e 's|"$||'
+        echo "$cd" | sed -e "s|.*filename\*=UTF-8''||" -e "s|.*filename\*=utf-8''||" -e 's|^"||' -e 's|";$||' -e 's|"$||'
         return
     fi
     if echo "$cd" | grep -q "filename=" ; then