HTML wallpapers
An HTML wallpaper is a small website running on the desktop through Lively’s web view. The official project describes clocks, audio visualizers, and pages that react to the cursor. You need the files, and you need to be comfortable that the page only does what you expect.
Do not load a random live webpage as wallpaper if you would not leave that page open in a normal browser all day.
Shader wallpapers
GLSL shaders draw motion on the GPU. Lively documents importing shaders, including Shadertoy-style sources, and exposing properties such as speed or color. Shaders can look striking at a small file size, but a complex shader can still load the GPU as much as a 4K video.
When to stay with MP4
If you only want a scene that already exists as video, use a video wallpaper. HTML and shaders are extra moving parts: they can break after a Windows or WebView2 update, and they are harder to share than one file.
This library
The current library on this site is mainly video loops. It is a companion to Lively, not a replacement for the app’s built-in shader samples.