PIL cannot set loop of GIF to 1

I am trying to convert a gif, first crop it then convert it into a gif which only loops once. It loops only once when I use Microsoft "Photo" app. However when on a html page it loops twice.I've tried changing loop = 0, but it makes the loop become infinite.

This is the code I am using:

from PIL import Image, ImageSequenceinput_gif = "input.gif"output_gif = "output.gif"crop_box = (0, 0, 300, 500)  # (left, upper, right, lower)with Image.open(input_gif) as gif:    frames = []    for frame in ImageSequence.Iterator(gif):        cropped_frame = frame.crop(crop_box)        frames.append(cropped_frame)    frames[0].save(        output_gif,        save_all=True,        append_images=frames[1:],        loop=1,        duration=gif.info.get("duration", 100),    )print("GIF cropped and saved successfully!")