For a non-Admin user, you cannot add a screen to "Favorite Screens" through the dashboard GUI pop-up, even though you can see the screen(s) AND add them through Monitoring --> Screens menu and clicking there on the + sign at the top right of the screen page.

Exact conditions to reproduce:

• use 2.2.0 (2.0.9 is ok in this regard)
• user should be "Zabbix User" level
• access to a hosts group should be "Read only"

If you try to add a screen, then popup shows "No screens found."

Similarly implemented slide-shows adding is ok in the scenario above.