Thumbnail not generated when attached the photo from mobile which is offline supported

By using Attach Content Control, I can add a photo to the page from my mobile phone, but the thumbnail is not shown as expected.

From the clipboard, I can see that the thumbnail of the attachment is always pyTextThumbnail.svg.

On the other hand, from the desktop channel, the thumbnail can be generated correctly.

My question is:

Can I also generate the thumbnail from the mobile?

It seems impossible to have the thumbnail on mobile, our business team decided to drop this requirement.