Yes, it's still "supported", although I really don't understand why. Roku usually drops a device into legacy status (no longer supported) between 8-10 years. I wouldn't be surprised for the 4200 to be dropped before the year ends, and perhaps a few more. Those older devices simply don't have the processing power and memory (both operating system memory and app storage) necessary for some of the newest apps and services. My personal opinion is its days are numbered.
I absolutely support checking it out as much as possible. Just trying to not get your hopes up for a solution.