Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 982)

C.Fn5
Clear all Custom Func. (C.Fn)
Selecting [ : Clear all Custom Func. (C.Fn) ] clears all Custom Function settings except
[ Customize buttons ] and [ Customize dials ].
Note
To clear settings configured with [ : Customize buttons ] and [ : Customize
dials ], select [ : Clear customized settings ].
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