Empty or missing type on genesis widget should not render an element/widget

Fixes #7153

core/modules/widgets/genesis.js

@@ -42,10 +42,15 @@ Compute the internal state of the widget
 GenesisWidget.prototype.execute = function() {
 	var self = this;
 	// Collect attributes
-	this.genesisType = this.getAttribute("$type","element");
+	this.genesisType = this.getAttribute("$type");
 	this.genesisRemappable = this.getAttribute("$remappable","yes") === "yes";
 	this.genesisNames = this.getAttribute("$names","");
 	this.genesisValues = this.getAttribute("$values","");
+	// Do not create a child widget if the $type attribute is missing or blank
+	if(!this.genesisType) {
+		this.makeChildWidgets(this.parseTreeNode.children);
+		return;
+	}
 	// Construct parse tree
 	var isElementWidget = this.genesisType.charAt(0) !== "$",
 		nodeType = isElementWidget ? "element" : this.genesisType.substr(1),

editions/test/tiddlers/tests/data/genesis-widget/EmptyType.tid

@@ -0,0 +1,14 @@
+title: Genesis/EmptyType
+description: Using an empty type attribute with the genesis widget
+type: text/vnd.tiddlywiki-multiple
+tags: [[$:/tags/wiki-test-spec]]
+
+title: Output
+
+<$genesis>Mouse</$genesis>
+
+<$genesis $type="">Mouse</$genesis>
++
+title: ExpectedResult
+
+<p>Mouse</p><p>Mouse</p>

editions/tw5.com/tiddlers/widgets/GenesisWidget.tid

@@ -1,6 +1,6 @@
 caption: genesis
 created: 20221101100729587
-modified: 20221101100729587
+modified: 20221230213912929
 tags: Widgets
 title: GenesisWidget
 type: text/vnd.tiddlywiki
@@ -21,6 +21,8 @@ The content of the <<.wlink GenesisWidget>> widget is used as the content of the
 |//{attributes starting with $$}// |Attributes starting with two dollar signs are appplied as attributes to the output widget, but with the attribute name changed to use a single dollar sign |
 |//{attributes not starting with $}// |Any other attributes that do not start with a dollar are applied as attributes to the output widget |
 
+<<.from-version "5.2.6">> If the `$type` attribute is missing or blank, the <<.wlink GenesisWidget>> widget does not render an intrinsic element, instead just rendering its children.
+
 Note that attributes explicitly specified take precedence over attributes with the same name specified in the `$names` filter.
 
 ! Examples