Generate or Refresh Flipsnack Link Preview Thumbnails

This article explains how link previews and thumbnail generation behave for external viewers on different platforms and provides steps to generate or refresh thumbnails for shared Flipsnack publications.

Summary

• Link preview generation varies by platform and device. Flipsnack generates a thumbnail when a flipbook is first published; external platforms may cache or fail to fetch that image depending on their crawler and device behavior.

How thumbnails are generated

• Flipsnack generates a thumbnail for a flipbook at first publish.
• If the flipbook’s first published version contains a blank cover page, the generated thumbnail may be blank and can persist even after republishing.
• Different platforms and devices may produce different results for the same link; preview generation can succeed on one device and fail on another.

Common causes of missing or incorrect previews

• Platform caching of link previews (social platforms may use a cached preview).
• Open Graph meta tags not set correctly.
• Cover image format, size, or aspect-ratio mismatches.
• The preview image not being accessible to the platform’s crawler.
• Device-specific behavior (some devices or apps handle preview generation differently).

Steps to generate or fix a thumbnail

1. Ensure the flipbook has a proper cover page with a designed image (PDF-generated cover) before publishing or create a copy, add a designed cover, and publish the copy so a valid thumbnail is created.
2. Clear local browser cache and cookies, or try a different browser or Incognito/Private mode.
3. Restart the browser and device; disable browser extensions temporarily and ensure the browser is up to date.
4. If sharing on social platforms, refresh the platform’s cached preview using their debug/inspector tools:
   • Facebook: Sharing Debugger
   • LinkedIn: Post Inspector
5. Confirm the publication’s Open Graph meta tags and that the cover image is accessible to external crawlers.

Platform-specific notes

• WhatsApp: Thumbnail generation is highly dependent on device and app behavior; the same link may show a thumbnail on one device and none on another. Using a different phone or device can sometimes produce a thumbnail.
• Facebook and LinkedIn: Provide tools to refresh their cached preview (Sharing Debugger, Post Inspector) which can force the platform to re-fetch updated metadata and images.

Troubleshooting checklist

• Verify the flipbook’s published cover is non-blank and correctly formatted.
• Create and publish a copy with a designed PDF cover if the original published with a blank cover.
• Clear browser cache and try a different browser or device.
• Use Facebook Sharing Debugger or LinkedIn Post Inspector to refresh cached previews.
• Check image size/aspect ratio and accessibility for crawlers.
• If issues persist after these steps, contact support for further investigation.

Conclusion Thumbnails for external viewers depend on the flipbook’s initial published cover, the target platform’s caching and crawler behavior, and the device used to view the link. Creating a proper cover before publishing and using cache-refresh tools on social platforms resolves many preview issues.