[Python] Plotly Image ignores alpha channel

I'm attempting to display a (semi) transparent image using plotly's go.Image object. I use cv2 to load the image from disk and convert it to rgba format. Following this issue, I manually set colormodel='rgba' but the resulting image still ignores the alpha value.

Example code:

import cv2
import plotly.graph_objects as go

original = cv2.imread(<path_to_image>)
original = cv2.cvtColor(original, cv2.COLOR_BGR2RGB)

transparent = cv2.cvtColor(original , cv2.COLOR_RGB2RGBA)
transparent[:, :, 3] = 127 # set to 255 // 2 for half-transparency

fig1 = go.Figure(go.Image(z=original))
fig1.show()

fig2 = go.Figure(go.Image(z=img2, colormodel='rgba'))
fig2.show()


Both fig1 and fig2 present the same image, but fig2 displays 4-channel pixels:

Seems like plotly cannot display transparent images. Is there a way to display the image with the alpha channel?

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