[Cin] Timeline borders

[preobraz at gmail.com]

Dear developers!

Now that you have done a tremendous amount of work to improve work with 
Cinelerra, you can pay attention to smaller issues. For example, to me 
personally, the border between the tracks is not at all obvious, 
especially when there are a lot of them. When the content is adjacent to 
the left side of the timeline, I understand where the border still 
somehow turns out (blue stroke). But in the absence of content, dealing 
with borders is much more difficult (red stroke).
Link: https://pic4a.ru/98/2zM.png

The proposals made were difficult for me, so I had to use an automatic 
translator.

Regards,
Ugin.