Error messages and warning messages in Operating Systems can either be useful or annoying. There never seems to be a middle ground. For example, Ubuntu empty trash can warning message: "Empty all of the items in the trash?" Not a usefull message especially when you need to confirm your intentions with a click. Fortunately you can easily disable the confirmation message in Ubuntu.
To suppress the confirmation warning, we need to turn off confirm_trash in the Configuration Editor, by opening a Terminal window and enter:
or from the menu, click on Applications \ System Tools \ Configuration Editor. If you do not see Configuration Editor, you can enable it in the menu editor by right-clicking on the Menu Bar and selecting Edit Menus
Then in Menu Layout, select System Tools, and in the right window pane select the check box for Configuration Editor.
Click the Close button (bottom) when finished.
Once Configuration Editor has opened, navigate to apps / nautilus / preferences and in the right window pane un-check confirm_trash. Close Configuration Editor.
Now when you empty the trash, the confirmation message will no longer prompt you to confirm.
NOTE: Be careful when making changes in Configuration Editor since there is no SAVE button and all changes you make are applied immediately.