Thank you for your quick reply. It was really a server side issue. The specific solution for Domino HTTP:
https://www.experts-exchange.com/articl … omino.html

After successful integration of Juicebox Pro  1.5.1 on IBM Domino server a have small issues on mobile devices running IOS 12.3 (Apple iPhone 8, iPhone7 etc.) After loading of the thumbnails by scrolling  the thumbnails flicker.The HTTP log shows that all thumbnails are fully reloaded by every scrolling. This happens by photo scrolling too - the photo flickers and then reloads again (according to the http log.). All configuration parameters in config.xml are set to default.
tested with Safari and  Chrome  on IOS 12.3
The problem does not  exist on any desktop browser on Windows (tested With Firefox, Chrome, Edge).

Please advise.