In Overview -> Settings -> User -> Manage SSH keys, when adding an existing key in the namespace whose key you are configuring, the UI indicates that a new key is saved with a randomly generated suffix; however, the key isn't actually created. If you navigate away and back again "Not configured" is displayed. 

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1. Add an existing key in the namespace whose key you are configuring
2. After clicking save the UI will display a new key with a random suffix
3. Navigate away and back

The UI displays "Not configured" instead of the secret name that was displayed previously. The key whose name was displayed was never created.

The existing key is configured instead of creating a new key with a random suffix.

It seems the bug caused by the design of adding key from another projects, some random strings are added to the key, this behavior should only happen while selecting key from another project. If it's the current project, it should use the same key name.