Fix legacy build

The build process failed because webpack does not allow failed imports
when it is run as a module.
This detects modules with default exports and only generates import
statements for default exports where they are available.

config/jsdoc/plugins/define-plugin.cjs

@@ -0,0 +1,33 @@
+/* eslint-disable import/no-commonjs */
+
+/**
+ * @fileoverview  This plugin extracts info from boolean defines.  This only
+ * handles boolean defines with the default value in the description.  Default
+ * is assumed to be provided with something like "default is `true`" (case
+ * insensitive, with or without ticks).
+ */
+
+const DEFAULT_VALUE = /default\s+is\s+`?(true|false)`?/i;
+
+/**
+ * Hook to define new tags.
+ * @param {Object} dictionary The tag dictionary.
+ */
+exports.defineTags = function (dictionary) {
+  dictionary.defineTag('define', {
+    canHaveType: true,
+    mustHaveValue: true,
+    onTagged: function (doclet, tag) {
+      const types = tag.value.type.names;
+      if (types.length === 1 && types[0] === 'boolean') {
+        const match = tag.value.description.match(DEFAULT_VALUE);
+        if (match) {
+          doclet.define = {
+            default: match[1] === 'true',
+          };
+          doclet.description = tag.value.description;
+        }
+      }
+    },
+  });
+};