The Multiple-actor Problem (MAP) occurs in a web application that contains multiple bits of code, each assuming that they are the only actor in the document. The problem manifests when these assumptions conflict with each other.
Some examples:
- A web app is written in framework A, then later an analytics script B is added. A makes assumptions about lifetime of elements and handling of events. B is not aware of these assumptions and subtly violates them, causing jank (example)
- A web app is written using framework A. Attempting to introduce a widgets built using framework B results in weird errors, because B is violating A's assumptions about control of document state (examples 1, [2](http://stackoverflow.com/questions/254