# Incorrect mime-types (content-type header) for mp4 and js

**URL:** <https://meta.discourse.org/t/incorrect-mime-types-content-type-header-for-mp4-and-js/257802>\
**Category:** Bug\
**Created:** [March 11, 2023, 3:27pm UTC](https://meta.discourse.org/t/incorrect-mime-types-content-type-header-for-mp4-and-js/257802 "2023-03-11T15:27:21Z")\
**Posts on this page:** 1\
**Showing post:** 15

<div class="post-metadata">

**Author:** ![nat](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/nat/32/235063_2.png) [@nat](https://meta.discourse.org/u/nat)\
**Post date:** [December 30, 2024, 3:49am UTC](https://meta.discourse.org/t/incorrect-mime-types-content-type-header-for-mp4-and-js/257802/15 "2024-12-30T03:49:18Z")

</div>

> [@Canapin](#):
>
> When loading the video URL, headers are different between a regular install and a dev install.
> 
> On the regular production install, the video content type is set to **application/mp4** , whereas it’s set to **video/mp4** on a dev install.

Oh good find - this is weird.

It looks like MiniMime (a library we use and own) might be returning these values

```plaintext
pry(main)> MiniMime.lookup_by_filename("a.mp4").content_type
=> "application/mp4"

```

> <https://github.com/discourse/mini_mime/blob/574c3bee73eba30db388f3dc0225311dcf303770/lib/db/ext_mime.db#L548-L550>

I’ll create a PR and we’ll discuss if it’s an issue changing these.

---

_[View the full topic](https://meta.discourse.org/t/incorrect-mime-types-content-type-header-for-mp4-and-js/257802)._