gui: Improve Receive Encrypted folder type requirements text (#7473)

The current text gives an impression that we are currently using a
Receive Encrypted folder, even if we are not. Thus, make the current
text displayed only when the folder is in fact Receive Encrypted, and
add a new string to be displayed when using different folder types.

Signed-off-by: Tomasz Wilczyński <[email protected]>

gui/default/untrusted/syncthing/folder/editFolderModalView.html

@@ -205,7 +205,7 @@
             <div class="col-md-6 form-group">
               <label translate>Folder Type</label>
               &nbsp;<a href="https://docs.syncthing.net/users/foldertypes.html" target="_blank"><span class="fas fa-question-circle"></span>&nbsp;<span translate>Help</span></a>
-              <select class="form-control" ng-change="setDefaultsForFolderType()" ng-model="currentFolder.type" ng-disabled="editingExisting && currentFolder.type === 'receiveencrypted'">
+              <select class="form-control" ng-change="setDefaultsForFolderType()" ng-model="currentFolder.type" ng-disabled="editingExisting && currentFolder.type == 'receiveencrypted'">
                 <option value="sendreceive" translate>Send &amp; Receive</option>
                 <option value="sendonly" translate>Send Only</option>
                 <option value="receiveonly" translate>Receive Only</option>
@@ -214,7 +214,8 @@
               <p ng-if="currentFolder.type == 'sendonly'" translate class="help-block">Files are protected from changes made on other devices, but changes made on this device will be sent to the rest of the cluster.</p>
               <p ng-if="currentFolder.type == 'receiveonly'" translate class="help-block">Files are synchronized from the cluster, but any changes made locally will not be sent to other devices.</p>
               <p ng-if="currentFolder.type == 'receiveencrypted'" translate class="help-block" translate-value-receive-encrypted="{{'Receive Encrypted' | translate}}">Stores and syncs only encrypted data. Folders on all connected devices need to be set up with the same password or be of type "{%receiveEncrypted%}" too.</p>
-              <p ng-if="editingExisting" translate class="help-block" translate-value-receive-encrypted="{{'Receive Encrypted' | translate}}">Folder type "{%receiveEncrypted%}" cannot be changed after adding the folder. You need to remove the folder, delete or decrypt the data on disk, and add the folder again.</p>
+              <p ng-if="editingExisting && currentFolder.type == 'receiveencrypted'" translate class="help-block" translate-value-receive-encrypted="{{'Receive Encrypted' | translate}}">Folder type "{%receiveEncrypted%}" cannot be changed after adding the folder. You need to remove the folder, delete or decrypt the data on disk, and add the folder again.</p>
+              <p ng-if="editingExisting && currentFolder.type != 'receiveencrypted'" translate class="help-block" translate-value-receive-encrypted="{{'Receive Encrypted' | translate}}">Folder type "{%receiveEncrypted%}" can only be set when adding a new folder.</p>
             </div>
             <div class="col-md-6 form-group">
               <label translate>File Pull Order</label>