Creating controls for visually controlling the TimeLine start and end frames number in Blender

In general, gizmos looks like arrows and circles on a 3D object with which we can move, rotate and scale the mesh. However, in Blender, the gizmo object is more versatile and can be used to suit our needs in different workspaces. For example, we can create a gizmo to adjust the start and end points of the timeline.

Changing the number of visible channels in Blender Video Editing

By default, there are 7 lines allocated for displaying channels with strips in the Blender user interface, in the Video Sequencer area. If all of them are not used in video editing, it will not be possible to hide unnecessary ones by simply scaling the area size.

However, this can be done by scaling the entire area interface.