Trail forking

[Gozala]

Going back and navigating elsewhere forks the trail

[Gozala]

This depends on #1281 once that's in place no special requirements are present as far as I can tell. In terms of UX I have few questions @patrykadas

1. Don't you think we need to have a visual clue, different from regular navigation to make the make the fact that we've forked the trail more clear ? Maybe instead of sliding the new page up into trail we should instead slide down the existing trail somehow ?
2. What happens with a trail where you navigated back ? Does past entry remains active or do we rewind it forward to point where you started going back to ?

[patrykadas]

@Gozala

1. I agree, we should provide visual clue to reinforce the spacial model.
   a) We could do it very simply, just by sliding it down, however It looks more like a trail switch, rather than fork:
   https://youtu.be/p-qJiHlfULE
   b) We could do it also more complex, I am just afraid that it takes too much time:
   https://youtu.be/Vlb8lSOvVrY
   I will keep experimenting with those.

2. I think that past entry should remain active, as soon as user did not clicked a new link - in this case we'd fork.

[Gozala]

I actually like the first one better, the second one looks very confusing. I wonder how it would look if we moved the former tab up as you have in first video and copy of it to the left at the same time, it may look quite messy or confusing as well.

[patrykadas]

@Gozala
I iterated a bit more on this, mostly played with animation curves and scale:

https://youtu.be/qVkg-XzXRv8

https://youtu.be/6XhcTN9JQWs