This is a small thing but a slight bug all the same. Basically, DietPi - running here on a Zero - when set to 1080P particularly on my tv (and seen on others), if I check the TV info or on booting it will report that it is actually running in 1080i. It seems to have existed since the earlier versions (I think 145 was the first I tried), is present in 150 and is 100% unique to DietPi rather than seeming to be hardware related. PC, BR players, a vast array of consoles and Raspbian, and any other OS available for the Pi (Kodi etc are all fine).
This can be fixed by the old hdmi_mode=16 being directly set in the config files, at which point DietPi will happily report the correct 1080P on bootup etc. Just thought it might be worth noting.