diff --git a/modules/restapi/src/main/resources/docspell-openapi.yml b/modules/restapi/src/main/resources/docspell-openapi.yml
index c9c1a6ed..3ef90ff3 100644
--- a/modules/restapi/src/main/resources/docspell-openapi.yml
+++ b/modules/restapi/src/main/resources/docspell-openapi.yml
@@ -1069,6 +1069,29 @@ paths:
               schema:
                 $ref: "#/components/schemas/BasicResult"
 
+  /sec/collective/previews:
+    post:
+      tags: [ Collective ]
+      summary: Starts the generate previews task
+      description: |
+        Submits a task that re-generates preview images of all
+        attachments of the current collective. Each existing preview
+        image will be replaced.
+
+        This can be used after changing the `preview` settings.
+
+        If only preview images of selected attachments should be
+        regenerated, see the `/sec/attachment/{id}/preview` endpoint.
+      security:
+        - authTokenHeader: []
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BasicResult"
+
   /sec/user:
     get:
       tags: [ Collective ]
diff --git a/modules/webapp/src/main/webjar/docspell.css b/modules/webapp/src/main/webjar/docspell.css
index 8dad246b..39b329ff 100644
--- a/modules/webapp/src/main/webjar/docspell.css
+++ b/modules/webapp/src/main/webjar/docspell.css
@@ -93,9 +93,6 @@
     padding: 0.8em;
 }
 
-.default-layout .ui.card div.image {
-    background: #fff;
-}
 .default-layout img.preview-image {
     max-width: 160px;
     margin-left: auto;