diff --git a/src/calibre/db/backend.py b/src/calibre/db/backend.py index 68e5570123..42e2f9d53f 100644 --- a/src/calibre/db/backend.py +++ b/src/calibre/db/backend.py @@ -422,7 +422,7 @@ class DB(object): def set_user_template_functions(self, user_formatter_functions): self._user_template_functions = user_formatter_functions - self._template_functions = formatter_functions().get_builtins() + self._template_functions = formatter_functions().get_builtins().copy() self._template_functions.update(user_formatter_functions) def initialize_prefs(self, default_prefs, restore_all_prefs, progress_callback): # {{{