TabbedDemo uses `addThemeVariants`, which is not available in some supported versions of the framework https://github.com/FlowingCode/CommonsDemo/blob/7022293e310c92743f67a4f69ce7d8c991ca38ec/src/main/java/com/flowingcode/vaadin/addons/demo/TabbedDemo.java#L374
TabbedDemo uses
addThemeVariants, which is not available in some supported versions of the frameworkCommonsDemo/src/main/java/com/flowingcode/vaadin/addons/demo/TabbedDemo.java
Line 374 in 7022293