I’ve been using this rack for two years now or more. Also requested it as a standard feature in Ableton library, but to no avail. So here it is, as simple as it gets: mid/side Audio Effect Rack. It consists of two channels, mid channel (width 0%) and side channel (width 200%). That’s all that was needed to make it work… once you know it. The reality is, not many people do.
Now it’s here for everyone to download and use.
Just use simple gain boost/reduction or put different effects in mid and side channel. Solo/mute channels to check mono compatibility. Or do some weird shit, it’s all up to you.