There are provided a method, a system and a computer program product for customizing a loading message to be displayed during a loading process. The system receives, from a client device used by a user, an event message that indicates a start of the loading process. The system receives, from the client device, one or more content sources. The system selects a content source among the one or more content sources. The system displays content from the selected content source to the user during the loading process.