Pane navigation hotkeys not fully functional

[Thulium-Drake]

Describe the problem:
Navigating around different panes while using the nav-pane-<DIRECTION> hotkeys can lead to interesting results

To Reproduce:
Consider this layout:

| 1 | 2 |
|---|---|
| 3 | 4 |

When using the pane-nav-<DIRECTION> hotkeys, one would expect the following possible moves:

1. 1-2
2. 1-3
3. 2-4
4. 3-4
   And their opposites.

But if the layout was made as follows:

|   1   |
|       |

1. Split vertical

| 1 | 2 |
|   |   |

2. Split 1 horizontal

| 1 | 2 |
|---|   |
| 3 |   |

3. Split 2 horizontal

| 1 | 2 |
|---|---|
| 3 | 4 |

The possible moves are:

1. 1-2 and back
2. 1-3 and back
3. 2-4 and back
4. 3-2
5. 4-1

I think this has something to do with how the panes relate to each other:

• 3 doesn't see 4 as it's neighbor, only 1 and 2
• 4 doesn't see 3 as it's neighbor, only 1 and 2

NOTE: if you use a different layout, all this stuff changes!