Frame Range Markers

When using Animtoolbox, it is possible to use markers as widgets to setup the frame range, instead of changing the frame range manually in the timeline it is possible to set it quickly using the markers.
It is available in the Timeline but also in the dopesheet and graph editor.

It works for the scene or preview frame range, but also for tools like editable motion curves and copy/paste matrices.

When using frame range markers it will create two markers named Frame_Start and Frame_End, which can be adjusted for the frame range.