Remove split view line when editing markdown in full screen

Features
1

Hi, I can see that the split view line between editor and preview is still present when you have open just the markdown editor. When you have the preview editor open it's not present though.
Example is this:
line

That line is a bit annoying in this scenario:

  1. Open Joplin Desktop on full screen and on your rightmost monitor
  2. Move the cursor at the right border of the screen, trying to move the scrollbar.
  3. The scrollbar doesn't move since the cursor picks the split line instead

Increasing the width of the scrollbar won't help of course.
I use Joplin Desktop 2.6.10 on Ubuntu 21.10.
Many thanks