I can tell you the black breakers are older. Newer FP breakers are white with colour-coded handles, green, red, blue, grey. They are very common panels in the west. I suspect the new breakers have improved tension in the contacts because they do not flop around like the old-timers do.
Blue handled 15a breakers without the hole in the handle, manuf 1996-97 were recalled by Schneider for possible failure to trip, sounds familiar?
It appears that the new panels for sale at Home Depot have gone back to all black breakers???
I’d call out this installation for possible amateur handiwork and let an electrician make the final call.