Makes a copy of the current state of this and saves it on an internal stack.
When [[email protected]] is called, this will be restored to the saved state. Multiple calls to [[email protected]] and [[email protected]] can be nested; each call to `gtk_snapshot_restore()` restores the state from the matching paired `gtk_snapshot_save()`.
It is necessary to clear all saved states with corresponding calls to `gtk_snapshot_restore()`.
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a `GtkSnapshot` |