Wrong MIME types for comic book formats

[rluetzner]

Independent of the file extensions, this library always returns application/x-cbr. This is incorrect, as there are specific MIME types for all the extensions, e.g. application/x-cbz or application/x-cb7.

To understand the impact, see the following issues in the Jellyfin project:

• Feature Request: Feed should differentiate between different comic book formats jellyfin/jellyfin-plugin-opds#38 and
• [Issue]: Wrong MIME type returned for different comic book formats jellyfin/jellyfin#11009

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Here's a tl;dr: cbr (a.k.a. Rar) is a proprietary compression algorithm, so most FOSS eReaders will not accept it. 🙂

[rluetzner]

Definitely something I can send a pull request for. 🙂

[rluetzner]

I just learned that application/x-cbr is deprecated. According to IANA, it should be

application/vnd.comicbook-rar and
application/vnd.comicbook+zip.