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While creating a new Progress Tracker
While on the Create Progress Tracker tab, scroll down to the Advanced section and open it by clicking the arrow
Press the Choose file button next to Add custom icon
Select a file from your device
The file’s name will be displayed next to the Choose File button
Press Save Changes
While editing an existing Progress Tracker
From the Edit Progress Tracker page, press Advanced to open the additional settings
Press Choose file to select an image
Press Save Changes