The BetaFeatures extension implements something similar, maybe it could be extended to work with Gadgets. But I'm not sure if it's a good idea, you could just use the dependency system to load other gadgets regardless.

In T55584#581617, @matmarex wrote:

The BetaFeatures extension implements something similar, maybe it could be extended to work with Gadgets. But I'm not sure if it's a good idea, you could just use the dependency system to load other gadgets regardless.

Except in cases where the user doesn't want to use that other gadget. In those cases, the dependent gadget should be greyed out and indicate they require the other component. This lets the editor/user decide.