Factorio Forums

Put an empty blueprint straight from the toolbar into the blueprint library (either 'My blueprints' or 'Game blueprints'). Then pickup that empty blueprint and select something to blueprint and set the name (yes I clicked the set name button), when you create the blueprint the name is gone. This also happens for blueprints in a book in the library.
Blueprints used this way from the inventory (either directly or from a book) DO work.

Thanks for the report. Issue will be fixed in 2.0.

Core of the issue is that blueprints in library are different objects than blueprints in inventory. When setting up that blueprint in library first a blueprint item is created but then it is cloned to blueprint record in the library. Common part of the blueprint (the blueprint content) is copied correctly however label is stored in a different place (blueprint items are item-with-label) and so the label had to be handled separately and it was not handled here.