File browser could have a standard hotkey/shortcut to go to the parent directory

[hippietrail]

Is your feature request related to a problem? Please describe.
On Mac all GUI software understands ⌘-↑ in file dialogs to go to the parent directory. Other OSes probably have a similar standard. When you're used to using it all the time it's annoying when it's not there and you have to reach for the mouse.

Describe the solution you'd like
Detect ⌘-↑ inside the main file loading dialog. At first just for Mac, others can be added when the Mac version works.

Describe alternatives you've considered
Putting up with having to use the mouse (-:

Additional context
I'm willing to work on this myself.

[dragonmacher]

This dialog is in need of a re-work. There is another ticket related to accessibility issues. At the very least the accessibility stuff needs to be addressed. I personally think its appearance is outdated as well. Not sure if/when I'll have the time, but fixing this up is on my mental list.