Arrow keys in move navigation on 2.16a

[Lingepumpe]

The Changelog for 2.16a says

Variations, arrows works when a variation is being displayed to show its movements. Left/Right = Previous/Next move. Up/Down = Previous/Next variation.

This is not working as expected at the ends of a variations:
If I press left arrow at the beginning of a variation, I expect it do go to the previous move in the game. Currently it goes to the first move of the previous variation (if it exists), or if you are at the first move of the first variation, left arrow is ignored.
A bit weird is also the behavior at the end of a variation line: If I press right arrow it jumps to the beginning of the next variation line (same as down arrow). I would have expected it to ignore the right arrow press instead.

Reproduction example: Create a new game, play:

1. d2-d4 d7-d5
   Press arrow back to go back to the position after whites move. Play alternative 1. ... Ng8-Nf6.
   This opens as variation, as expected. Try pressing left arrow to go back to the position after whites move, it doesn't work, you are "stuck" in the variation.

[lukasmonk]

One solution could be that the jump between variations and main movement could be done by pressing Shift with an arrow.
I have updated it in my beta.

[Lingepumpe]

To me the most important point is, if I press arrow left (back one move), it should always lead to a position of a half move ealier than the current position. This is also how it works on various other chess tools I checked for consistency, left arrow at the beginning of a variation will give you the position before the initial move starting the variation was made.