In the episode where Lt. Dangle and another guy get drunk in Dangle's squad car, the man asks "What gun is that? Is that a Glock?" Lt. Dangle replies "Yes, it's a Glock 9mm." His gun is in fact a Beretta 92fs, not a Glock.
A few minutes before Deputy Johnson is proposed to, you are able to see a shadow of a cameraman on the closed door on the right of the screen. However, this sort of thing occurs in many episodes and isn't a goof since the characters know they are being filmed and occasionally even speak directly to the camera operators.