You can auto-hide any toolbar in Opera after enabling it via keyboard shortcut or mouse gesture or button.
Keyboard shortcut / Mouse gesture
Create new keyboard shortcuts or mouse gestures in Application section with following action codes.
Toolbar
Action code for keyboard shortcut or mouse gesture
Menu bar
Enable menu bar & Delay, 12000 & Disable menu bar
Main bar
View main bar, 6 & Delay, 10000 & View main bar, 0
Personal bar
View personal bar, 6 & Delay, 12000 & View personal bar, 0
Tab bar
View page bar, 6 & Delay, 10000 & View page bar, 0
Address bar
View address bar, 6 & Delay, 10000 & View address bar, 0
Navigation bar
View navigation bar, 6 & Delay, 10000 & View navigation bar, 0
View bar
Set alignment, “Document view toolbar”, 6 & Delay, 8000 & Set alignment, “Document view toolbar”, 0
Status bar
View status bar, 6 & Delay, 12000 & View status bar, 0
To modify auto-hide time, change Delay, X value (time in milliseconds) in above code.
To hide/show a toolbar without auto-hide use the following.
Toolbar
Action code for keyboard shortcut or mouse gesture
Menu bar
Enable menu bar | Disable menu bar
Main bar
View main bar, 6 | View main bar, 0
Personal bar
View personal bar, 6 | View personal bar, 0
Tab bar
View page bar, 6 | View page bar, 0
Address bar
View address bar, 6 | View address bar, 0
Navigation bar
View navigation bar, 6 | View navigation bar, 0
View bar
Set alignment, “Document view toolbar”, 6 | Set alignment, “Document view toolbar”, 0
Status bar
View status bar, 6 | View status bar, 0
Button
You can add buttons to any toolbar (main bar, tab bar, address bar, navigation bar, view bar, status bar, start bar or panels) except menu bar & personal bar simply by dragging button links to required place. Clicking on the button links without dragging will add the buttons to Tools → Appearance → Buttons → My Buttons for later use.
When you try to add a button, a dialog box with following message will popup. Press OK to add button.
Adding new button with action
[Action]
Do you want to proceed?
To remove a button, right-click on it and select Remove From Toolbar.
Get buttons for above from here as Opera button links won’t work in Opera Watch (WordPress).