Better handling of thumbnails

Summary


Let us set a few default thumbnail sizes (the only ones that a user could request from the server, the others should not be allowed) and automatically generate those thumbnails when the pictures are uploaded.

Basic Example


_No response_

Motivation


The problem this fixes is that generating pictures in thumbnail sizes is generally quite slow, much too slow for a normal user.

Detailed Design


Create a thumbnail section in the Settings page, let's set several if needed, different sizes and formats.

Requirements List


not needed

Drawbacks


No drawbacks.

Alternatives


No alternatives? The problem this fixes is that generating pictures in thumbnail sizes is generally quite slow, much too slow for a normal user.

Adoption Strategy


It's a very minor change, that should be opt-in.

Unresolved Questions


_No response_