Override the Default HST Component Class
By default when no hst:componentclassname is configured on a page component, the delivery tier (a.k.a. HST) uses the built-in component class org.hippoecm.hst.core.component.GenericHstComponent.
It is possible to override this default component class by adding the fully qualified classname of your default HstComponent in the hst-config.properties configuration file as follows:
The hst-config.properties file is typically located in the site/src/main/webapp/WEB-INF directory in a project.