Bug 1653334 added a null check to prevent the crash here. More importantly, I believe, the changes there means we shouldn't offer the choice of printing a Selection when we don't support it.
Bug 1653981 Comment 8 Edit History
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Bug 1653334 added a null check to prevent the crash here. More importantly, I believe, the changes there mean we shouldn't offer the choice of printing a Selection when we don't support it.