On a side and an FYI:
Just in case you didn't know, in settings, at the URL opera://settings/themes, you can set your Opera wallpaper to your desktop's wallpaper.
Also, specfically in Opera GX, if you goto the URL opera://settings/early_bird, enable the Live Wallpaper Helper (just it if you don't want anything else there), restart Opera, goto the URL opera://settings/live_wallpapers and install the helper, you can set live wallpapers from https://store.gx.me/mods/?tagAlias=desktop%2Clive that you have installed in Opera as your desktop wallpaper.