The Save button would remain “grayed out” / unavailable. I needed to change the name (like just adding a space, which gets stripped off anyway) to allow the Save.
I’ve done some testing of this today. It seems that as soon as you choose a file to upload it will be set as your organization logo. The save button continues to be greyed out since the logo has already been saved.
The UI is confusing and it is not clear that this save of the logo has occurred. I will take a look at getting that corrected. Thank you for the report Matt!!