Background switching only support Page and Profile these two types of links. We do not support the upload of background images for other link types. You can choose the frosted glass effect of the avatar as the background image.
To add switch background image follow these simple steps:
1.Go to link customize page,click Theme editor on the top
2.On the theme editor page,you can switch background by default or your profile image
Now that you've selected background image it will show up on your InstaBio page.