To show your key inputs on screen, e.g. for a screencast or screen sharing, you can use screenkey Show archive.org snapshot .

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

• Prevents you from data breaches and liability risks
• Upgrade at your own pace
• Works with modern Rubies

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A really useful flag is --show-settings. Running screenkey --show-settings shows a settings window, which allows you to easily adjust the key overlay.
The option Select window/region is especially useful for choosing where the overlay is placed.