I built two separate Firefox extensions which are fundamentally incompatible with each other. The incompatibility is by design, as it would be totally unlogical for a user to install both. While I can stress out in the doc that both shouldn't be used at the same time, I don't trust the user to read the doc, and I'm looking for a way that one extension could detect the presence of the other and either disable itself or the other one (ideally while popping an error message).
Is there a way for an extension to be aware of the presence of another extension? I know it's possible for an extension to specify it depends on another one, but what I need is the exact opposite, a way for an extension to specify it conflicts with another one.