don't fall back to json dict for text that only contains latin-1

background-script.js

@@ -140,12 +140,22 @@ function json_lookup_arbitrary_as_is(dict, text)
 }
 function json_dict_any_as_is(text)
 {
+    let maybe_found_non_latin = false;
+    for(let i = 0; i < text.length; i++)
+    {
+        let codepoint = text.codePointAt(i);
+        if(codepoint > 0x100)
+            maybe_found_non_latin = true;
+    }
+    if(maybe_found_non_latin)
+    {
         for(let dict of json_dicts)
         {
             let ret = json_lookup_arbitrary_as_is(dict, text);
             if(ret !== undefined)
                 return ret;
         }
+    }
     return undefined;
 }