nextcloud / nextcloud/server

Allow more preview formats

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#13,552 77 comments 39 reactions 1 assignee View on GitHub

@sorbaugh is already working on this.

Since Sep 30, 2025.

❄️ 2026-Winter 1. to develop enhancement feature: previews and thumbnails performance 🚀
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Description

Right now we serve previews in png or jpg. Which has the advantage of being support on nearly every platform since the late 90s. But of course it is no longer the best solution out there.

I would propose to allow different image formats. The top candidate in my opinion is webp. This allows for smaller images at comparable quality. Of course the backend would need to distinquis what to server but I'm sure we can solve that with some js magic to set the accept headers ;)

This doesn't mean we fully get rid of the jpg an png as older firefox and IE versions do not support it. But I bet this could be performance boost especially when using a lot of images.

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