diff --git a/ui/jquery.ui.accordion.js b/ui/jquery.ui.accordion.js
index 0cc1f9e2a..c6b33befb 100644
--- a/ui/jquery.ui.accordion.js
+++ b/ui/jquery.ui.accordion.js
@@ -486,9 +486,11 @@ $.extend( $.ui.accordion, {
 			$.each( fxAttrs, function( i, prop ) {
 				hideProps[ prop ] = "hide";
 
-				var parts = ( "" + $.css( options.toShow[0], prop ) ).match( /^([\d+-.]+)(.*)$/ );
+				var parts = ( "" + $.css( options.toShow[0], prop ) ).match( /^([\d+-.]+)(.*)$/ ),
+					// work around bug when a panel has no height - #7335
+					propVal = prop === "height" && parts[ 1 ] === "0" ? 1 : parts[ 1 ];
 				showProps[ prop ] = {
-					value: parts[ 1 ],
+					value: propVal,
 					unit: parts[ 2 ] || "px"
 				};
 			});