I do believe that some fonts are not compatible with the Lr Book module. I would duplicate your "Saved Book Collection" (to enable experiment) and try to set a single 'global' font that is compatible. Ctrl+Alt+A (or Menu>Edit>Select all text cells), and the set a font in the Lr Type panel. From my notes_ Not all system fonts are available to LR. Not all fonts in LR are in the system.!!! A full understanding of fonts that Lightroom uses is a mystery! In general- LR uses the fonts installed in your system, But- With exceptions- I think it is limited to true-type fonts? And- I can see fonts in Lightroom that are not in the Windows "Fonts" folder!? eg. {Bickham Script Pro} is available as type in the LR Book module, but it is not in my Windows font folder. C:\Windows\Fonts (and Photoshop, earlier versions?, may have installed a PS font folder, not available to LR! )
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