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One of the keys on my XPS 13 9310 has become unreliable and sometimes needs to be pressed extra-hard to ensure it registers.  It *might* just be that a bit of dirt or debris has slipped under the key cap, but the laptop is still under warranty so I don't want to risk pulling off the key cap to clean it in case I break the key and void the warranty. Can anyone suggest the correct course of action?  Are the key caps easy to remove without damage?
Unreliable key on XPS 13 (9310)