Vizlib Collaboration supports profile images for users on comments for a better appearance of the Vizlib Collaboration box.
This is achieved via Qlik's Content Library, where you can define avatars for your users.
Value provided in this property should match the Qlik Sense Content Library where images are stored. Image themselves has to be named using following pattern: <USER_ID>.<USER_DIRECTORY>.png
So for instance if you have a user MY_COMPANY\Admin, a valid file name would be 'Admin.MY_COMPANY.png'
If there is no image for given user in the Content Library or Content Library does not exists, default avatar will be used. Default avatar consists of two first letters of the user name (online version) or proper user initials (enterprise only).