TL,DR: A trend indicator with deviation bands using a modified Donchian calculation
This indicator plots a trend using the average of the lowest and highest closing price and the lowest low and highest high of a given period. This is similar to Donchian channels which use an average of the lowest and highest value (of a given period). This might sound like a small change but imho it provides a better "average" when lows/highs and lowest/highest closing prices are considered in the average calculation as well.
I also added the option to show 2 deviation bands (one is deactivated by default but can be activated in the options menu). The deviation band uses the standard deviation (of the average trend) and can be used to determine if a price movement is still in a "normal" range or not. Based on my testing it is fine to use one band with a standard deviation of 1 but it is also possible to show a second band with a different deviation value if needed. The bands (and trendline) can also be used as dynamic support/resistance zones.