Preserve the previous state of the "Load from Epidata API" dialog in subsequent uses of it (that is, save the selections made and text entered into fields). This would be particularly useful when a bad request is made, so that an error can be corrected instead of filling out everything again. It would also be helpful, for instance, in comparing the same signal between different geos.

It naively "seems" easy enough to do this within a browser session by not resetting certain JS variables between instantiations of the dialog. It could also be handy to retain them across different sessions using cookies, if not too difficult.