fix: #122

application/source/dom/util/init-options-from-attributes.mjs

@@ -64,8 +64,12 @@ function initOptionsFromAttributes(element, options, mapping = {}, prefix = "dat
                 value = mapping[optionName](value);
             }
 
-            const typeOfOptionValue = typeof finder.getVia(optionName);
-            if (typeOfOptionValue === "boolean") {
+            const optionValue = finder.getVia(optionName);
+                
+            const typeOfOptionValue = typeof optionValue;
+            if (optionValue === null || optionValue === undefined) {
+                value = null;
+            } else if (typeOfOptionValue === "boolean") {
                 value = value === "true";
             } else if (typeOfOptionValue === "number") {
                 value = Number(value);