Enhancing File Space Keyboard Navigation

Two areas of navigational flexibility that feel difficult to me, in the current design, are temporal (the ability to go backwards and forwards in time with regards to editing history) and contextually spatial (using the current file list as a sequential mechanism for stepping from one file to the next).

Basing additional navigational movement upon these two axes would provide the user with the following capabilities:

* The main thing I find myself struggling with is being unable to return to where I was. The way I work, I often find myself switching between two or three items in order to draft something. Perhaps this is a rewrite and I have the old version available to reference, or a response to an email that is also listed. Or maybe I'm writing something that causes an idea and I want to jot down a stub to develop later. Whatever the case may be, if you go off to do something else, you may want a way of easily getting back to where you were.

There are some challenges with the idea. Does history record every single file you cross paths with while using arrows in the note list, or does it only record files you activate the editor on, through any means? I could see either making sense, though for my purposes I think maybe the latter works better.

* Use of the file list as a short-term workspace or checklist (to mention a couple of ideas off of the top of my head). If you search for someting that results in five related items, and they are all relevant to what you are currently working on, then flicking between those files effortlessly is essential. One can do this with the mouse, but being able to step forward or backward in this list in a stepwise fashion from the keyboard is I believe invaluable.

- Currently one can use the following technique: `⌘L` + `↑` | `↓` + `↩`
- This idea would add two menu commands somewhere (they could even be organised into the same submenu as history, as it's kind of the same sort of thing) that select the next or previous file in the current file list, relative to the current selection. This could be bound to shortcuts by default, or it could be left up to the user to do so.
- Switching between files from the editor context would restore the cursor to where it was (just like the current method does).

This approach might also address: https://multimarkdown.zendesk.com/hc/en-us/community/posts/360046335853-Feature-request-keyboard-shortcuts-to-navigate-between-panes as there would be a lessened need to actively switch focus directly into the file list if the main reason for doing so (switching files) can be done directly.