I can't even fathom what kind of design issue causes both Ctrl keys to stop working—though sometimes work again briefly—with the problem persisting after the keyboard is changed, and the same problem being observed on two different thinkpads 8 years apart! https://forums.lenovo.com/t5/ThinkPad-T400-T500-and-newer-T/T410-both-CRTL-keys-not-working/m-p/4617200#M139597 …
Is a bug triggered in some NSA or CCP spy mode firmware that tries to intercept the Ctrl key to check for secret magic key combinations for their spies to get privileged access? At this point, that's my best explanation.
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