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For creators

File attachments + previews

Drop any file into a batch post. The right preview renders automatically — images, videos, audio, PDFs, anything.

Last updated May 20, 2026

How to attach

Click Attach in the batch Common Room composer and pick any file (multi-select supported). Each upload uses the same R2 pipeline as course thumbnails and lesson assets, so files end up on your CDN with a permanent URL.

Type-aware previews

  • Images (PNG / JPG / GIF / WebP / AVIF / SVG) → inline thumbnail; click to open fullscreen.
  • Videos (MP4 / WebM / OGV / MOV) → inline <video> with native HTML5 controls + picture-in-picture.
  • Audio (MP3 / WAV / OGG / M4A) → audio widget under the filename.
  • PDFs → embedded preview iframe + a download chip beneath.
  • Anything else → download chip with the filename + file size.

Empty bodies are allowed

You can post a file with no commentary — drop a slides PDF and hit Post. The composer accepts body-only, attachment-only, or both.

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