The mirror moved by itself when you enlarge or decreased the screen chart because it is actually anchored dynamically somewhere! I know that kind of indicator and used to try it in the past on that platform, but I do not remember its name. Because if we don’t know how it should be anchored, I can’t help.
If you don’t feel that it is important on the way it should be anchored (because I still don’t why and how you are using it), the easy way would be to use the mean of the last X candles (we can’t retrieve automatically the quantity of bars displayed on the screen while zooming).
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