In this tab, lazy load settings can be specified for a publisher.
Fetch margin (in percentage of viewport) - how fast (how early before being in viewport) an ad should be fetched to an ad slot (ad request should be made)
Render margin (in percentage of viewport) - how fast (how early before being in viewport) an ad should be displayed (creative should be displayed)
Mobile scaling - multiplier of Render and Fetch margins for mobile devices