try with separate step

.drone.yml

@@ -66,13 +66,26 @@ steps:
       repo: dessalines/lemmy
       auto_tag: true
       auto_tag_suffix: linux-amd64
+    when:
+      ref:
+      - refs/tags/*
+
+  - name: build latest development version and push to docker hub
+    image: plugins/docker
+    settings:
+      dockerfile: docker/prod/Dockerfile
+      username:
+        from_secret: docker_username
+      password:
+        from_secret: docker_password
+      repo: dessalines/lemmy
+      tags:
+        - dev
     when:
       branch:
         include:
           - main
           - drone-release-main
-      ref:
-      - refs/tags/*
 
   - name: push to docker manifest
     image: plugins/manifest