i have a website and i open a popup containing my other website. if a user has alexa toolbar on his browser, Can Alexa watch that popup website or just the main webpage?
Because Alexa is a browser plugin, it can access anything the browser reads (within the limits of the plugin API). I'd assume it registers the visit to the popup as well, even though the toolbar might not show in the popup window. For example Adblock Plus, a popular firefox plugin, also blocks ads in popups, even though it's button is not always visible in there.
I'd say it's pretty much dependant on the implementation and choices made by the developers