Problem: Beachballing Description

If you have a Time Machine backup created prior to its installation, now is the time to use it: Restore your Mac from a backup - Apple Support.

If you do not have a Time Machine backup, create one: Back up your files with Time Machine on Mac - Apple Support.

Contact the developer for uninstallation instructions: https://www.tynsoe.org/geektool/

Regrettably, a reply has been made to this discussion advertising a product you do not need nor should you install. Do not install it.

Kalzamel wrote:

I used Geektool application, then I deleted it, but the app's icon is still on Mac's menu bar, and when I put my cursor on it, the cursor starts spinning (beachballing).

I would look for an official uninstaller to remove your third party applications.

Look for any built in or in-app uninstaller and use that.

Typically this would be in the "About" or "Preferences" of the app.—it may require reinstalling to officially uninstall.

If in doubt—If in doubt refer to the developers website; Support/Help/FAQ/known issues/compatibility/updates:

Contact a third party vendor

Contact a third-party vendor - Apple Support

Sometimes the app's uninstaller will also be within the app's folder in the "Applications" folder and sometimes it may be hidden within the app bundle itself.

Keep in mind usually if an app has you run an installer when you first get the app, then you need to run an uninstaller to completely remove the app. If an app has you drop it onto the Applications folder to install it, then usually just deleting the app from the Applications folder is sufficient. I believe the latter is also true for Apps installed through the Apple App Store.

You may need to reinstall it to properly uninstall. There may be a built in uninstaller in the install dmg. Check this out.https://osxuninstaller.com/uninstall-guides/uninstall-geektool-mac/