Here's a screenshot showing the settings to activate, along with what it looks like with multiple racks visible:
It would be great if we could get official support for this somehow... Or even the ability to cascade the racks across a wider window, instead of scrolling them. But that may take more work. The author should be able to support multiple racks being visible like this by tweaking the app manifest.
You know that if you have the app set to allow screen rotation, and you're working in portrait mode, then you can already see multiple rack slots?
I do know about that setting, but it's not possible to "rotate" the windows in Chrome OS Android runtime. What we really need here is support to resize the windows arbitrarily.