set canRemix and canSaveAsCopy

src/views/preview/preview.jsx

@@ -545,7 +545,8 @@ Preview.defaultProps = {
 };
 
 const mapStateToProps = state => {
-    const projectInfoPresent = Object.keys(state.preview.projectInfo).length > 0;
+    const projectInfoPresent = state.preview.projectInfo &&
+            Object.keys(state.preview.projectInfo).length > 0 && state.preview.projectInfo.id > 0;
     const userPresent = state.session.session.user !== null &&
         typeof state.session.session.user !== 'undefined' &&
         Object.keys(state.session.session.user).length > 0;
@@ -558,15 +559,15 @@ const mapStateToProps = state => {
         state.session.session.user.id === state.preview.projectInfo.author.id;
 
     return {
-        canAddToStudio: isLoggedIn && userOwnsProject,
+        canAddToStudio: userOwnsProject,
         canCreateNew: true,
-        canRemix: false,
+        canRemix: isLoggedIn && projectInfoPresent && !userOwnsProject,
         canReport: isLoggedIn && !userOwnsProject,
-        canSave: isLoggedIn && (userOwnsProject || !state.preview.projectInfo.id),
-        canSaveAsCopy: false,
+        canSave: isLoggedIn && (userOwnsProject || !projectInfoPresent), // can save a new project
+        canSaveAsCopy: userOwnsProject && projectInfoPresent,
         canShare: userOwnsProject && state.permissions.social,
         comments: state.preview.comments,
-        enableCommunity: state.preview.projectInfo && state.preview.projectInfo.id > 0,
+        enableCommunity: projectInfoPresent,
         faved: state.preview.faved,
         fullScreen: state.scratchGui.mode.isFullScreen,
         // project is editable iff logged in user is the author of the project, or