If approaching the Qt Quick Timeline module not from the Design Studio side but as an ordinary Quick module, without prior knowledge of its types and usage,  the documentation has serious shortcomings.

The main issue is that there are no code snippets or samples, making it very difficult to understand how the classes are intended to be used.

Also the module has not a single example.

The properties documentation often do not mention the default value and/or indicate if this property in practice needs to be set or is optional.

The terms "keyframes" and "keyframe groups" are used inconsistently / interchangeably.