Updating a plugin by ticking its checkbox through the plugin manager, followed by hitting the update button, removes the ability to interact with the checkbox, as the plugin is now prepared for an update during the next reboot of Jenkins, as intended.

If you revisit the page at at later point and head to the bottom of the page and select "None", the preselected box loses the tick, when it should be immutable to further selection actions, as the plugin is already prepared for an update.

See the attachment for visual steps to replicate that.