Create a desktop shortcut, for example:
webpTest.desktop with
[Desktop Entry]
Version=1.0
Type=Application
Comment=
Exec=/usr/bin/Thunar
Icon=SOME_VALID_PATH_TO_A_webp_IMG
Path=SOME_VALID_PATH
Terminal=false
StartupNotify=false
You’ll notice that webp image format is not taken into account, while ok with png or jpg
Manjaro XFCE lacks by default the tiny (15Kb) GitHub - aruiz/webp-pixbuf-loader: WebP Image format GdkPixbuf loader