Config commands in Saved/Config/Windows/Input.ini are ignored

I added a Jump input action to my project, and I see a corresponding line show up in DefaultInput.ini:

+ActionMappings=(ActionName="Jump",Key=SpaceBar,bShift=False,bCtrl=False,bAlt=False)

I figured I could override this in the Input.ini file, so I put the following commands there:

-ActionMappings=(ActionName="Jump",Key=SpaceBar,bShift=False,bCtrl=False,bAlt=False)
+ActionMappings=(ActionName="Jump",Key=E,bShift=False,bCtrl=False,bAlt=False)

But when I hit the play button in my editor, the jump action is still mapped to spacebar. Is anyone else experiencing this? What could be going wrong here?

I saw better results with the following syntax for my Input.ini file:

[/Script/Engine.InputSettings]
ActionMappings=(ActionName="Jump",Key=E,bShift=False,bCtrl=False,bAlt=False)

However if I don’t include all action mappings (e.g. sprint, crouch, etc), I find that I am unable to use them, despite them being set in the default input file. So going forward I would have to make sure that all action mappings are mentioned in this file.