gui: Fix add folder bug (fixes #6930) (#6931)

gui/default/syncthing/core/syncthingController.js

@@ -76,6 +76,7 @@ angular.module('syncthing.core')
             order: "random",
             fileVersioningSelector: "none",
             trashcanClean: 0,
+            versioningCleanupIntervalS: 3600,
             simpleKeep: 5,
             staggeredMaxAge: 365,
             staggeredCleanInterval: 3600,
@@ -1764,7 +1765,7 @@ angular.module('syncthing.core')
             $scope.currentFolder.simpleKeep = $scope.currentFolder.simpleKeep || 5;
             $scope.currentFolder.staggeredCleanInterval = $scope.currentFolder.staggeredCleanInterval || 3600;
             $scope.currentFolder.staggeredVersionsPath = $scope.currentFolder.staggeredVersionsPath || "";
-            $scope.currentFolder.versioningCleanupIntervalS = $scope.currentFolder.versioningCleanupIntervalS || 0;
+            $scope.currentFolder.versioningCleanupIntervalS = $scope.currentFolder.versioningCleanupIntervalS || 3600;
 
             // staggeredMaxAge can validly be zero, which we should not replace
             // with the default value of 365. So only set the default if it's

gui/default/syncthing/folder/editFolderModalView.html

@@ -144,7 +144,7 @@
               <span translate ng-if="folderEditor.externalCommand.$error.required && folderEditor.externalCommand.$dirty">The path cannot be blank.</span>
             </p>
           </div>
-          <div class="form-group" ng-if="currentFolder.fileVersioningSelector == 'none'" ng-class="{'has-error': folderEditor.versioningCleanupIntervalS.$invalid && folderEditor.versioningCleanupIntervalS.$dirty}">
+          <div class="form-group" ng-if="currentFolder.fileVersioningSelector != 'none'" ng-class="{'has-error': folderEditor.versioningCleanupIntervalS.$invalid && folderEditor.versioningCleanupIntervalS.$dirty}">
             <label translate for="versioningCleanupIntervalS">Cleanup Interval</label>
             <div class="input-group">
               <input name="versioningCleanupIntervalS" id="versioningCleanupIntervalS" class="form-control text-right" type="number" ng-model="currentFolder.versioningCleanupIntervalS" required="" min="0" max="31536000" aria-required="true" />