Merge pull request #664 from yolouiese/636-responsive-breakpoint-switcher-fix-bugs

#636: Responsive breakpoint switcher - Fix bug on snapshot resize

Author: omiroshnichenko

app/code/Magento/PageBuilder/view/adminhtml/web/css/source/_mobile-viewport.less

@@ -6,6 +6,7 @@
 
 .mobile-viewport {
     &.pagebuilder-stage-wrapper {
+        &.stage-content-snapshot,
         &.stage-full-screen {
             .pagebuilder-stage {
                 .pagebuilder-canvas {