The invention provides methods and devices that address problems encountered when attempting to accurately reconstruct visual stimuli being displayed to a user as they interact with online-content, typically through a browser interface. In one embodiment, the invention provides for the browser to maintain a record of selected technical parameters and relevant data that may impact the manner in which online-content is being displayed to the user, taking into consideration the current context in which the browser is being operated. In another embodiment, the invention is a device for recording events as reported from a browser interface. The events are recorded in a selected format and syntax to form a primary index of events and related outcomes which comprise the user's interface experience. In operation, the device detects events as detected at the browser interface. Next, the device identifies, categorizes, and filters detected events as to their relevance to the visual stimuli being presented to the user. The device then assigns a unique identifier, preferably in the form of an alphanumeric string, to each relevant event. Furthermore, the device records selected events into a log (along with their categorization), a unique identifier, and the time in which the event occurred. Yet another embodiment is a device that records changes in parameters that may impact the visual stimuli.