New answers tagged profile-picture
It's not a bug or any corruption in your smartphone. It's one of gmail features. Try opening your mails on a desktop browser and you will see the same result as in gmail of your smartphone.
The bug appears to be related to corruption between the gmail and hangouts profiles that are supposedly synchronized. Updating the picture in hangouts fixed the issue, even though that is supposedly shared with gmail and updating in gmail left two versions.
Looks like a bug. You should report it to Google directly (see how here).
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