The NLA editor is in need of a design overhaul, hopefully for 3.1 or 3.2.
This should be a project on itself, however, the worst offender currently is the use of
gradients on strips. Something that can be fixed easily.
{F11390293, size=full, loop, autoplay}
A simple replace of `UI_draw_roundbox_shade_x` for `UI_draw_roundbox_4fv` brings strips
in line with how other areas are drawn.
This patch also:
* Remove embossed lines around active action channel.
* Highlight the strip while being moved.
This patch does not include any theme changes. This will be tackled separately.
Reviewed By: HooglyBoogly
Differential Revision: https://developer.blender.org/D12968
4758a7d357