The Zoom indicator allows you to see how the price behaved inside the selected bar. Moving the vertical line on the indicator chart, on other open charts of the same symbol with a smaller timeframe, the period will be highlighted with a rectangle.

For example, you can open a chart window with a daily timeframe and place the Zoom indicator in this window . In the external parameters, you can only set the color of the vertical line (Line Color) and the color of the rectangle (Area Color). The second chart window should be with a smaller timeframe. This can be any of the timeframes available in the terminal, which are less than the daily one in this case. Next, when you move the vertical line in the window with a smaller timeframe, the area whose bars are included in the bar on which the vertical line is located will be highlighted with a rectangle.

You can open several windows with charts with smaller timeframes relative to the chart on which the indicator is located. 

Description of the Zoom indicator on my blog