Add missing space in .backface-visibility definition; fixes #17873

[ci skip]

diff --git a/less/mixins/vendor-prefixes.less b/less/mixins/vendor-prefixes.less
index afd3331c31da856f226b354916e21ebad9d3311a..cc5c15eb66257d3509dc7dad94ef9c48f19a4636 100644 (file)
--- a/less/mixins/vendor-prefixes.less
+++ b/less/mixins/vendor-prefixes.less
@@ -54,7 +54,7 @@
 // Prevent browsers from flickering when using CSS 3D transforms.
 // Default value is `visible`, but can be changed to `hidden`
 
-.backface-visibility(@visibility){
+.backface-visibility(@visibility) {
   -webkit-backface-visibility: @visibility;
      -moz-backface-visibility: @visibility;
           backface-visibility: @visibility;