Question: Disable Messages' "Logged In.aiff" sound
Every time my Mac wakes up in my account, it makes a left-to-right, rising spaceship sound. I'd rather it didn't.
Thanks to drfrogsplat's instructions on macos - What is causing this sound on my Mac? - Ask Different, I identified that the sound is /Applications/Messages.app/Contents/Resources/Logged In.aiff. Thanks to macOS' protections, I can't delete that.
I could uncheck "Play Sound Effects" in Messages, but that also disables "Message received sound." I'd like to hear of new messages but not hear that Messages is working normally. Wouldn't many people?
Know a way to do that?
If it helps: the services I use are Apple's and Gmail / GTalk.
MacBook Pro (Retina, 13-inch, Early 2013), macOS Sierra (10.12.6)