The reason for this question is for informational purposes, also to provide the beginning reader with the correct path to follow if you intend to display a png image without a background, in a tkinter window. Try wm_attributes ("-transparentcolor", " ")
, but it is not an absolute and correct solution. Thank you very much for your patience and recommendation.
from tkinter import Tk,Frame,Label,PhotoImage
root = Tk()
image = PhotoImage(file="image.png")
frame = Frame(root)
label = Label(frame, image=image)
label.pack(side="bottom", fill="both")
frame.pack(side="bottom", fill="both")
root.wm_attributes ('-transparentcolor', 'black')
root.mainloop()