There is a general use case to be able to compare any combination of test/page data from a particular Product/Repository (also called branch) on top of the equivalent data from any other Product/Repository combination. One specific example would be comparing any test/page combination from "Firefox Firefox-Non-PGO" to "Firefox UX-Non-PGO" To accomplish this in the UI, the following steps will be carried out. 1.) Add a "Compare To" select menu that contains the complete list of Product/Repositories. When a particular combination is selected, it will be added as an additional data series to whatever set of graphs is currently displayed. 2.) This "Compare To" series will persist if a user continues to navigate to other test/page combinations or time slices. It will also behave identically to other datapoints displayed on the graphs. 3.) An additional control will be provided to allow a user to modify the color of the "Compare To" data series.
These changes are now in production. Marking this as resolved.