Fix dummy processing

safe/converter.py

@@ -332,7 +332,9 @@ def encoder(
             val = str(starting_num) if starting_num < 10 else f"%{starting_num}"
             # we cannot have anything of the form "\([@=-#-$/\]*\d+\)"
             attach_regexp = re.compile(r"(" + re.escape(attach) + r")")
-            scaffold_str = attach_regexp.sub(val, scaffold_str)
+            # check if we have at least 2 matches, if not, we have a dummy
+            n_matches= len(attach_regexp.findall(scaffold_str))
+            scaffold_str = attach_regexp.sub(val, scaffold_str) if n_matches > 1 else scaffold_str.replace(attach, "*")
             starting_num += 1
         # now we need to remove all the parenthesis around digit only number
         wrong_attach = re.compile(r"\(([\%\d]*)\)")