71692abd59
The issue was that with a96f1208cc the clamping
of the `View2D` happened in the drawing function
of the channel list. That of course won't work if the
channel list isn't drawn.
The fix is to ALSO clamp in the drawing function of
the main area. The reason this has to be in addition, is that
(I think) the channel box is drawn first. So if the clamping doesn't
happen there, the channels and their keys can lose their vertical
alignment.
Pull Request: https://projects.blender.org/blender/blender/pulls/129864