diff -r 6ef41443211e -r 85b6f13f1088 src/lib/XMLContentHandler.h
--- a/src/lib/XMLContentHandler.h	Thu Jul 22 01:06:14 2021 +0200
+++ b/src/lib/XMLContentHandler.h	Thu Jul 22 20:01:03 2021 +0200
@@ -28,6 +28,15 @@
 
 	virtual ~XMLContentHandler() = default;
 
+	/**
+	 * @param uri identifier of the option
+	 * @param value value of the option
+	 * @return whether this option is supported and was applied here
+	 */
+	virtual bool setOption(const std::string& uri, const std::string& value) {
+		return false;
+	}
+
 	// FIXME: namespaces, check names
 
 	virtual void writeStartElement(const std::string& name, const std::vector<std::string>& attributes = {}) = 0;