Hello Olli,
since Vaadin flow 14.8.4 it seems this component does not longer work correctly.
java.lang.NoSuchMethodError: org.jsoup.nodes.Element.traverse(Lorg/jsoup/select/NodeVisitor;)Lorg/jsoup/nodes/Element;
at com.vaadin.flow.component.polymertemplate.TemplateDataAnalyzer.inspectTwoWayBindings(TemplateDataAnalyzer.java:244)
at com.vaadin.flow.component.polymertemplate.TemplateDataAnalyzer.parseTemplate(TemplateDataAnalyzer.java:233)
at com.vaadin.flow.component.polymertemplate.TemplateInitializer.lambda$null$23ee5b4f$1(TemplateInitializer.java:91)
at com.vaadin.flow.internal.ReflectionCache.lambda$wrapValueProvider$d0062d93$1(ReflectionCache.java:93)
at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1660)
at com.vaadin.flow.internal.ReflectionCache.get(ReflectionCache.java:110)
at com.vaadin.flow.component.polymertemplate.TemplateInitializer.<init>(TemplateInitializer.java:92)
at com.vaadin.flow.component.polymertemplate.PolymerTemplate.<init>(PolymerTemplate.java:91)
at com.vaadin.flow.component.polymertemplate.PolymerTemplate.<init>(PolymerTemplate.java:106)
at org.vaadin.olli.FileDownloadWrapper.<init>(FileDownloadWrapper.java:28)
at org.vaadin.olli.FileDownloadWrapper.<init>(FileDownloadWrapper.java:49)