So I just received my S6 and I was wondering what that little bubble with the 3 dots pop ups when I'm in messaging apps mean? I'm kinda baffled by it, and btw this phone is amazing!
Do you have the Toolbox feature enabled? It's weird that it only pops up in your messaging app though, if it was the Toolbox, that floats around all the time. It's like a quick access toolbar to let you start an app without going to the App Drawer.
That is a floating menu button. It shows up on apps that have a menu. This is to account for older apps that don't have a menu button due to the menu button was part of the hardware in previous Android version . most apps now have a menu option within the app,
Yup, there should be a setting somewhere. I don't have an S6, but if it's in the same place as the Tab S or Note 4, it's under Settings, Device, Toolbox.
Also, if you tap and hold on the button, the EDIT and REMOVE options should appear.