We've gotten several (18 at last count!) questions about what to do if your viewing mode suddenly changes to an outline, or tree, mode.

The way to remedy this is to go to the top right of the screen and click on options, and under Display Modes, click on Standard, as shown with the red arrow in this picture.


Now just for fun, here's a good listing of all the places (that I could find after searching for only a few minutes) where this question was asked)