Seconding this request. We can just use the CTRL+ALT+Del then lock, but considering how much we do it, it would be really nice to do it with one click then exit the session. Thanks for consideration!
We'll keep this as a feature request, but I wanted to also mention Lock on Disconnect. You can turn this option on by downloading the Advanced Configuration Editor from the Extension Marketplace. Navigate to the Configuration tab on the Admin page -> Application Configuration -> Quick Settings.
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