1 files changed, 9 insertions, 1 deletions
diff --git a/src/css/curCSS.js b/src/css/curCSS.js
index 59a639f68..6d8b6a2d3 100644
--- a/src/css/curCSS.js
+++ b/src/css/curCSS.js
@@ -1,9 +1,12 @@
 import jQuery from "../core.js";
 import isAttached from "../core/isAttached.js";
 import getStyles from "./var/getStyles.js";
+import rcustomProp from "./var/rcustomProp.js";
+import rtrim from "../var/rtrim.js";
 
 function curCSS( elem, name, computed ) {
-	var ret;
+	var ret,
+		isCustomProp = rcustomProp.test( name );
 
 	computed = computed || getStyles( elem );
 
@@ -11,6 +14,11 @@ function curCSS( elem, name, computed ) {
 	if ( computed ) {
 		ret = computed.getPropertyValue( name ) || computed[ name ];
 
+		// trim whitespace for custom property (issue gh-4926)
+		if ( isCustomProp ) {
+			ret = ret.replace( rtrim, "$1" );
+		}
+
 		if ( ret === "" && !isAttached( elem ) ) {
 			ret = jQuery.style( elem, name );
 		}