body default display is always block. @mikesherov was right and this is the proof. Fixes #10227

src/css.js

@@ -9,7 +9,7 @@ var curCSS, iframe, iframeDoc,
 	rnumsplit = new RegExp( "^(" + core_pnum + ")(.*)$", "i" ),
 	rnumnonpx = new RegExp( "^(" + core_pnum + ")(?!px)[a-z%]+$", "i" ),
 	rrelNum = new RegExp( "^([-+])=(" + core_pnum + ")", "i" ),
-	elemdisplay = {},
+	elemdisplay = { BODY: "block" },
 
 	cssShow = { position: "absolute", visibility: "hidden", display: "block" },
 	cssNormalTransform = {

test/unit/css.js

@@ -560,6 +560,24 @@ test( "show() resolves correct default display, detached nodes (#10006)", functi
 	div.remove();
 });
 
+test("show() resolves correct default display #10227", function() {
+	expect(2);
+
+	jQuery("html").append(
+		"<p id='ddisplay'>a<style>body{display:none}</style><p>"
+	);
+
+	equal( jQuery("body").css("display"), "none", "Initial display: none" );
+
+	jQuery("body").show();
+
+	equal( jQuery("body").css("display"), "block", "Correct display: block" );
+
+	jQuery("#ddisplay").remove();
+
+	jQuery.cache = {};
+});
+
 test("toggle()", function() {
 	expect(9);
 	var div,