How to overlay a chart of one currency pair on a chart of another currency pair?

The comarison panel allows you to overlay several charts on one. It is located above the main chart.

Click on the appropriate icon and a window will open in front of you. Then just enter the pair,which chart you need to compare 

Enter the desired pair, select it. Next the price dynamics of the selected pair will be displayed on the top of the current chart.
In the "Add tool" tab, you can add a whole chart, for this you need to go to this tab and select the desired pair in the search.

The interface will look like this

In order to remove new charts, click on the cross located in the upper left corner of the chart