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For examples of extensions using this hook, see Category:BSUEModulePDFBeforeAddingStyleBlocks extensions . Category:Extension hooks#BSUEModulePDFBeforeAddingStyleBlocks Category:Undocumented extension hooks#BSUEModulePDFBeforeAddingStyleBlocks Category:Extension hooks provided by UEModulePDF Category:Extension hooks#BSUEModulePDFBeforeAddingStyleBlocks Category:Undocumented extension hooks#BSUEModulePDFBeforeAddingStyleBlocks Category:Extension hooks provided by UEModulePDF