Jump to source between projects

We've got several projects (multi-module maven, if it matters). Project B depends on modules in project A, but is a separate project for a variety of reasons. 

When I have both projects open (in separate IDEA windows), I'm looking for a way to jump to the source in project A from the usage in project B, instead of jumping to a tab in project B containing the .class file (yes, I have sources attached, but can't edit them).

Is there a way to do this? If not, is this a feature that would be useful to others (outside my team)? One of my teammates mentioned that other JetBrains tools are able to find an open project, so it seems like it would be possible to implement.