go build -gcflags=-m=2 . 2>&1 | less
RenderF This doesn't need to return .Bytes(), we can use the output (*bytes.Buffer) This is Redundant.
Panel Change []Line to []*Line Otherwise adding to Lines is a Copy/Makes more garbage. (!)
Line I'd like NewLine to take (narg... any), to init:
Text
RenderF
UpdateF
Width
DefaultColor (the 2nd "text" item)
And have NewLine return *Line.