It's impossible to save webp images that behave like stickers in Telegram for Android.
I don't believe this is intended behavior. In Desktop, I can right click them and "Save As". In iOS (for iPad), I can select them and tap the "Share" symbol to have them be downloaded on my device. On Android, there is no option whatsoever that allows for downloading, either by tapping nor pressing down (as shown by the images).
Considering that having certain webp images behave like stickers is considered "intended behavior", I believe this issue should be addressed, as it makes it unreasonably hard to share webp images while preserving the transparency layer (compressing the image deletes it).
Steps to reproduce
Using Telegram Desktop, send an uncompressed webp image that behaves like a sticker (cannot understand the precise pattern, but images smaller than 2000x2000px usually have this behavior on my end) in any chat.
Open Telegram for Android and navigate to the chat.
Tapping on the sticker-like image will bring up "Reply, Add to Favorites, Forward, Pin, Delete".
Long pressing on the sticker-like image brings up the options to delete it, reply to it, and forward it.
There is no option to download the shared image on the Android device.
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