I am just coming near the end of a project and decided to move a couple unwanted pages to the trash. A moment later the contents layout on the left had suddenly changed so I now have an item on the left called Binder that is dropped down from the top. I can no longer access the trash or any of my resources either.
Does anybody know why this happened and how I can get it back to normal? It’s unnerving when something like this happens when you have close to 100,000 edited words in place.
Right-Click on the grey bar that says Draft and then click on the Unhoist Binder option
And then maybe click the Collections button up on the toolbar as well.
The right click to unhoist recovered the trash and resources but the binder was still there so I clicked the collections bar and suddenly I have a green sheet there with no sign of the previous contents.
OK Clicking on binder has brought the list of contents back but this is looking like a mess.
If you click the Collections icon in the toolbar, the collections will toggle to hidden and everything should look normal again.
Can I buy you a virtual drink? That’s a huge relief 
The crazy part about all this is that I’ve been using Scrivener now regularly for 3 years but I just don’t use 99% of the features. I only really use folders to create new chapters and then add pages within the folders.
You’re not alone; Someone else came to the forums because his daughter accidentally turned on revisions colors, and so all new text was turning purple. Some features are worth learning about just so you can turn them off once you stumble upon them.
I kind of wish there was a way to mass-disable keyboard shortcuts, with the option to turn them back on in groups based on what features you’re actually using. But Mac OS just isn’t designed that way.
That part you could effectively do using the Keyboard System Preference pane’s Modifier Keys… button, and set them all to “No Action”. 
Might be a little “scorched earth” for what you want though!