Signal-ios: Unable to paste images in latest iOS from e.g. Imgur

[fracture-point]

Bug description

I often paste images that are long-press-copied from websites, e.g. Imgur. Something has changed recently (within the last ~3 weeks) such that this almost always fails now with the message "Unable to remove metadata from image". It seems to arise from the code added here - https://github.com/signalapp/Signal-iOS/pull/2907/files. The only workaround is to screenshot the image + crop, which is clunky and time consuming.

Steps to reproduce

• Long-press copy an image from a website, e.g. imgur
• Context-menu paste into a Signal Chat + press send
• The screen very quickly flashed the error "Unable to remove metadata from image" and then goes back to an empty message editor (no image).

Actual result: The image is not sent.

Expected result: The image is sent.

Device info

Device: iPhone Xr

iOS version: 14.0.1

Signal version: 3.18

Link to debug log

https://debuglogs.org/8ecbbeb85eb6b5f0264bf9bc7a10853179b56b9ed82c0b2e465d5486a8095c86.zip

[FaultyJuggler]

Can confirm currently happening

[fumiakiy]

The root cause of this issue is the same as the other issue #4572 ; Copying an image in iOS 14 Safari copies the WebP image as WebP.

[h4knet]

Here is a video of the bug:

https://user-images.githubusercontent.com/1595901/104000791-0d511680-519f-11eb-89c3-1be07e3bfbfe.mp4

As we can see, the error message also disappear instantly, so it's hard for a regular user to read and understand the issue.