I've been reading through the new information about UXP and the announcement that it will be replacing CEP.

If this happens it will likely mean the end of our current CEP extension, since the support provided in UXP does not cover our use case. To be specific we have problems with the following areas:

1) Most critical UXP is "not a browser" and as such will only support a subset of HTML. Our extension relies on being able to run another web application within the browser control supplied by CEP, in an iframe window. While there is currently no list of supported HTML, it seems likely that iframe will not be a supported HTML element.

This will break our CEP extension.

2) No support for persistent panels. Currently there is only support for Modal Dialogs, which are expect to be invoked and then closed. Our CEP extension relies upon a persistent control, which the user logs into once.

3) In ability to access the user file system, in particular the Download directory. This will break a few features in our application which rely on being able to read information from this directory.