@leocg Nah, it's kinda pop on/off sounds. Like notifications, but nothing really happened. I wonder if when a streamer on twitch change the game they are playing make a sound cause i have my sidebar logged. I checked if when a streamer goes online make any sound, but nah.

My browser just plays various notification sounds but i don't have any idea of what about is it.
I don't have GX Control enabled and i'm sure the sound is coming from Opera GX, i closed all programs and the sounds still plays when i left Opera open...