Charts in OH3

Hello,

I have a question about the formatting of the values in the chart. both the values at the min/max values and the tooltip are unformatted. I have already created metadata for this and made a formatting there with %.0f W, this is also displayed to me when I look at the item itself, but in the chart everything remains the same. Am I doing something wrong? or is that like the widgets that you distinguish in yaml somewhere in state and the displayed state? For help I would be very grateful.

Furthermore, I can not find anything about charts where you could look up what there is still so for things that do not go through the menu but directly in yaml. Where can I find some additional information or a guide to all the different possibilities? Maybe someone could explain how e.g. the chart Building Pages in the OH3 UI: documentation draft (1/3) is assembled.

Thanks a lot!