Minimum width for right pane is annoying

[pierricgimmig]

There is a minimum width to the right pane that can be greater than half the screen width. This means that the right pane is either completely hidden, or that that it takes up more than half the horizontal space, with nothing in between. We should allow for arbitrary width.

[florian-kuebler]

I haven't checked the code, but it seems that the maximum is somehow computed (or a fixed number of pixels). On my widescreen, the minimum width is more like one quarter of the screen, while when reducing the window size, it reaches the half.

@reichlfl Do you know about the reasoning about this decision?

[reichlfl]

I don't know why this is the case. It should be fine to allow arbitrary widths, or at least significantly reduce the minimum width.