Tiny thing. This always happens after an update to pamac. It won´t show in the tray anymore after login. Tried changing settings and removing pamac and its config, then reinstalling. Still no luck. It just won't show anymore. Happens on all DE's I've ever run with Manjaro: XFCE, Budgie, MATE, and now Cinnamon. Just can't seem to figure out why this always happens and why nothing seems to fix it, not even delaying it's start with 3 or 5 seconds. So weird.
btw, I say always because I have another machine that I test every "release" on, fresh. And always as soon as pamac gets updated, no more pamac-tray icon. Htop shows pamac-tray runs. It just isn't in the tray any more.