# Mp4 files are downloading instead of displaying inline

**URL:** https://meta.discourse.org/t/mp4-files-are-downloading-instead-of-displaying-inline/396363
**Category:** Bug
**Created:** [18 februari 2026 om 07:38 UTC](https://meta.discourse.org/t/mp4-files-are-downloading-instead-of-displaying-inline/396363 "2026-02-18T07:38:21Z")
**Posts on this page:** 1
**Showing post:** 2

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### Author: ![Canapin](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/canapin/32/119591_2.png) [@Canapin](https://meta.discourse.org/u/Canapin)
#### Post date: [18 februari 2026 om 08:58 UTC](https://meta.discourse.org/t/mp4-files-are-downloading-instead-of-displaying-inline/396363/2 "2026-02-18T08:58:22Z")

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For the record, there was a topic about it and Nat worked on the matter:

> [@Incorrect mime-types (content-type header) for mp4 and js](https://meta.discourse.org/t/incorrect-mime-types-content-type-header-for-mp4-and-js/257802/16):
>
> Just a quick update - The ext\_mime\_db above that we use follows IANA Media Types defined here - [https://www.iana.org/assignments/media-types/media-types.xhtml](https://www.iana.org/assignments/media-types/media-types.xhtml). Unfortunately, this means that mp4 is correctly application/mp4 sweat_smile Though, looking into our S3 uploader implementation further, I do see that we are adding [Content-Disposition](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition) header "attachment" for pretty much every upload that is not an image, but it feels like it was only intended…

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