How do I rename files without a right-click?

Solution 1:

  1. Select (click on) the file, and press F2
  2. The filename will be highlighted as shown below; simply type the new name and press Enter to rename the file.

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Solution 2:

If your HUD is enabled, press Alt to show its prompt, write rename (or the equivalent translation in your Ubuntu idiom) and press Enter to rename. Of course, you have to select the file and/or folder before.