To show the tab indicator arrow you have to enable the Active Tab Indicator Arrow option from the Display Options. 

1. Navigate to WP Tabs Pro → Click on Add New to Add New Tab Group.

2. Type a Title for your tab group.

3. Select any tab type you want from the Tabs Type option. Two options are available:

• Content
• Post

4. Under the Display Options you will find the Active Tab Indicator Arrow option. Click on the Show button to enable it. 

Note: To show this tab indicator, you should set the margin between tabs and description from the Margin Between Tabs and Description option below.

• Screenshot: (Active Tab Indicator Arrow)