Support for Videos and Galleries as Post Thumbnails (Featured Media)

[kaffeeringe]

WordPress is a powerful tool for content management, but its core functionality limits how media can be displayed as post thumbnails (or "featured images"). Currently, only single images are supported as featured media. This creates a gap for press offices, social media teams, and content creators who want to:

• Use videos (e.g., short clips, teasers, or event highlights) as engaging entry points for their posts.
• Display galleries (e.g., image carousels) directly in post previews, similar to Instagram or Pixelfed.
• Leverage ActivityPub to seamlessly cross-post rich media to the Fediverse without losing visual appeal.

As a result, many teams default to platforms like Instagram for simplicity—even though WordPress could serve as a central hub for their content if it offered comparable flexibility.

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Proposed Solution

Extend WordPress Core to support videos and galleries as featured media, with the following capabilities:

1. Videos as Featured Media

• Allow users to set a video (e.g., MP4, WebM) as the featured media for a post.
• Support an optional custom thumbnail for the video (falling back to a frame from the video if none is provided).
• Ensure compatibility with:
  • Embedded players (e.g., YouTube, Vimeo) via oEmbed.
  • Self-hosted videos (with responsive playback).
  • ActivityPub plugins, so videos appear correctly when shared to the Fediverse.

2. Galleries as Featured Media

• Enable galleries (e.g., image carousels) to be set as featured media.
• Display galleries in a swipeable format (like Instagram or Pixelfed), showing one image at a time with navigation controls.
• Support:
  • Touch/swipe gestures for mobile users.
  • Keyboard navigation (left/right arrows) for desktop users.
  • Lazy loading for performance.

3. Backward Compatibility

• Retain the existing "featured image" functionality as the default.
• Add a new meta box in the post editor to select the type of featured media (image, video, or gallery).
• Ensure themes can opt into supporting these features via template tags (e.g., the_post_video(), the_post_gallery()).

4. UI/UX Improvements

• Update the Media Library to allow bulk selection of images for galleries.
• Add a preview pane in the post editor to see how the featured media will appear in archives, homepages, and ActivityPub shares.
• Include fallback options for themes that don’t yet support these features (e.g., display the first image of a gallery or the video thumbnail).

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Use Cases

1. Press Offices:
   • Share event highlights as video thumbnails on the homepage, with the full post containing a write-up and additional media.
2. Social Media Teams:
   • Post image carousels directly to WordPress and have them appear as swipeable galleries in Fediverse clients (via ActivityPub).
3. Bloggers and Creators:
   • Use short video teasers as featured media to increase engagement on archive pages.

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Technical Considerations

• Performance: Ensure videos and galleries are optimized for fast loading (e.g., lazy loading, responsive sizing).
• Accessibility: Add ARIA labels for gallery navigation and video controls.
• Theme Support: Provide hooks and filters for theme developers to customize the display of featured media.
• REST API: Extend the REST API to include featured media type and associated data (e.g., video URL, gallery images).

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Mockup

Here’s a rough idea of how the post editor could look:

Featured Media:
[ ] Image   [x] Video   [ ] Gallery

Video:
[ Upload Video ] or [ Enter URL ]
Thumbnail:
[ Upload Thumbnail ] or [ Select from Video ]

Gallery:
[ Select Images ] (Bulk upload from Media Library)
[ Reorder Images ] (Drag and drop)

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Why This Matters

• Unifies workflows: Teams can create content once and publish everywhere (WordPress + Fediverse) without sacrificing visual appeal.
• Reduces platform dependency: Encourages users to centralize their content in WordPress instead of siloed platforms like Instagram.
• Future-proofs WordPress: Aligns with modern content consumption trends (video, interactive media).

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Examples

You can see a bit what I would like to produce on these sites:

• ​https://dotcomslave.de/
• ​https://ulfdaude.de/

[westonruter]

Being able to use a video as a post's featured media was previously discussed in #43117 and #41127. It was closed as wontfix.

I don't think the "featured media" is going to be the right solution here, especially blocks. I would think that a site wanting this feature should rather do something like designate a Group block as the featured container (e.g. as the first block in the content), within which any block can be added. This could then be extracted when listing out the posts, like an excerpt.