gtk-builder-tool: Avoid a crash with <placeholder/>
Not sure we can do much with a ui file that has elements littered throughout. But at least we can avoid crashing while trying to convert it.
Fixes: #3781 (closed)
Not sure we can do much with a ui file that has elements littered throughout. But at least we can avoid crashing while trying to convert it.
Fixes: #3781 (closed)