I thought we were once told we could cite for suction cup windshield mounted stuff (aux. mirrors, GPS devices, radar detectors, etc.). At the time I thought it was ironic because the patrol cars had a suction cup mounted note pad attached to the windshield.
CALIFORNIA CODES
VEHICLE CODE
26708. (a) (1) No person shall drive any motor vehicle with any
object or material placed, displayed, installed, affixed, or applied
upon the windshield or side or rear windows.
CALIFORNIA CODES
VEHICLE CODE
26708. (a) (1) No person shall drive any motor vehicle with any
object or material placed, displayed, installed, affixed, or applied
upon the windshield or side or rear windows.

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