What are role Icons and what do they mean?

Role icons allow you to display scores for multiple roles that you have played in mythic + keystones on your character. Here is an example of the tooltip with and without secondary roles:

 

To enable role icons, you'll need to do the following:

1. Log into World of Warcraft.
2. Type /rio.
3. Scroll down to General Tooltip Options.
4. Click the box to the right of Show Role Icons in Tooltips.
5. Click Save at the bottom of the window.

How do I get an alt role to show on my tooltip?

Once you've reached at least 40% of your character's overall score, you will see an opaque role icon for that role. In the example at the top of this article, the example on the right displays a solid role icon for the main role (healer) and an opaque icon for the alt role (dps). If an alt role reaches at least 80% of the overall score, it will show that role icon as a solid role icon instead, similar to your main role icon.

Can I choose to display my main role icon, but not my alt role icon?

No. Once you choose to display role icons, it will show icons for all relevant roles if they meet the requirements of at being at least 40% of your main role's score.