true, you can't do this:
But you can do this:
make the mcp_volbg.png a transparent file (no actual image).
created fader image with enough space between the 2 arrows to fit the meter.
The Meter is still on top, so you will not be able to control the fader in center where the meter is.
The design is impractical if you need wide meter.
There are several themes that just use a triangle slider on one side or the other.
That's probably less confusing.
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