if you've been wondering about some features of Iris have you checked the FAQ? You can find the link on the About menu (https://github.com/irislib/faq).
Iris search box is also useful for quick answers if it's a common question.
quotingBlue = a followed user with NIP05 identifier.
nevent1q…p6r6
White = you don't follow but 1-10 of your following follows the user (hover over the icon and Iris shows the count)
Yellow = you don't follow but over 10 of your following follows the user (hover over the icon and Iris shows the count)
https://github.com/irislib/faq/#color-badges-on-user-names