shepetal's app icon, favicon, avatar and indicator pictures use the 🤫 (U+1F92B, shushing face)
from Noto Color Emoji by Google.

Source:  https://github.com/googlefonts/noto-emoji/blob/41e31b110b4eb929dffb410264694a06205b7ad7/svg/emoji_u1f92b.svg
License: Apache License, Version 2.0 (LICENSE-Apache-2.0.txt in this folder, the repository's license at that commit)
Copyright Google LLC

emoji_u1f92b.svg is the unmodified source file. The shepetal files place it on their own grounds
and render it to PNG, ICO and ICNS; the artwork itself is not changed.