Notch player overlay mode

[paix64]

Hi, first of all thank you for this amazing bar!

I was just thinking it would be great to see the name of the song and audio visualizer at the same time. I think it looks neat. Code just got little bit messy, but it works with no problem.

Example:

[Axenide]

Hey, that looks good. Hmm... Did you know that you can change what it shows by doing middle-click in the icon? (In this case Firefox). It will cycle between visualizer, title and artist. I can't test right now but how does that behave with this change?

[paix64]

Yeah... I didn't know about the middle click feature, it is broken let me try to fix that. Also is there a wiki or something there is so many features I just discover lol.

[Axenide]

There isn't but I'll write one soon lol

[paix64]

Seems that when I initialize the stack and make it the center_child (of mpris_small if I remember correctly), the overlay just can't be seen. I tried to change the center_child to overlay on the go. Middle click behavior works now but overlay is just a black screen, I don't know if there is a problem I cannot see because I'm not used to the GTK.

[its-darsh]

This looks ugly, it needs some extra care (e.g. radial gradient underneath the text fades from center to out).