Coffee and Toast
If you go to Photoshop CC > Preferences > Interface, you can change the Colour Theme under the Appearance section by clicking on one of the four colour chips, ranging from dark grey to light grey, to alter the workspace appearance.
If you hold the Shift + Alt keys and then click on one of the colour chips, you won’t change the Colour Theme effects, but the colour chips themselves are replaced by pieces of toast, ranging from very dark toast up to white toast. Choose your preferred toast to alter your workspace brightness.
While the toast is visible, press Shift + Cmd and then click on a piece of toast, it will change to cups of coffee of varying strengths to represent the colour theme choices. You can hold Shift + Alt again and click on the colour chips to change it back to the original grey.
On the toolbar are three small dots representing the Edit Toolbar function. Click and hold over this icon and the small fly-out menu will appear. Click on it to open the edit panel. Hold the Shift key and click Done and where the three dots were before, a banana will appear. The banana will stay there until you use Edit Toolbar again, press Shift and click Restore Defaults.
Now we just need the monkey to go with the banana. Open or create a Photoshop document with layers in it and then go to Window > Layer Comps. This opens a small Layer Comps panel. Click the Menu icon and choose New Layer Comp. Name the new layer ‘Layer Monkey 0’ and click OK to add a new layer comp. It might require a click to activate, but when you do, the icon on the left of the panel will turn into a cheeky monkey! Rename it anything else to return to normal.