Remove the NPAPI plugin from the webapp.

remoting/webapp/manifest.json.jinja2

 {
   {{ MANIFEST_KEY_FOR_UNOFFICIAL_BUILD }}
   "name": "__MSG_PRODUCT_NAME__",
   "version": "{{ FULL_APP_VERSION }}",
   "description": "__MSG_PRODUCT_DESCRIPTION__",
   "manifest_version": 2,
   "default_locale": "en",
   "minimum_chrome_version": "32",
   "app": {
 {% if webapp_type == 'v1' %}
@@ skipping 24 matching lines @@
         "{{ THIRD_PARTY_AUTH_REDIRECT_URL }}"
       ],
       "js": [ "cs_third_party_auth_trampoline.js" ]
     }
   ],
   "content_security_policy": "default-src 'self'; script-src 'self' {{ TALK_GADGET_HOST }}; style-src 'self' https://fonts.googleapis.com; img-src 'self' {{ TALK_GADGET_HOST }}; font-src *; connect-src 'self' {{ OAUTH2_ACCOUNTS_HOST }} {{ GOOGLE_API_HOSTS }} {{ TALK_GADGET_HOST }} https://relay.google.com",
 {% endif %}
   "optional_permissions": [
     "<all_urls>"
   ],
+
+{% if webapp_type != 'v1' %}
+  "oauth2": {
+    "client_id": "{{ REMOTING_IDENTITY_API_CLIENT_ID }}",
+    "scopes": [
+      "https://www.googleapis.com/auth/chromoting https://www.googleapis.com/auth/googletalk https://www.googleapis.com/auth/userinfo#email"
+    ]
+  },
+  "sandbox": {
+    "pages": [ "wcs_sandbox.html" ]
+  },
+{% endif %}
+
   "permissions": [
     "{{ OAUTH2_ACCOUNTS_HOST }}/*",
     "{{ OAUTH2_API_BASE_URL }}/*",
     "{{ DIRECTORY_API_BASE_URL }}/*",
     "{{ TALK_GADGET_HOST }}/talkgadget/*",
     "https://relay.google.com/*",
     "storage",
     "clipboardRead",
     "clipboardWrite",
     "nativeMessaging"
@@ skipping 10 matching lines @@
         "tcp-connect",
         "tcp-listen",
         "udp-send-to",
         "udp-bind",
         "udp-multicast-membership",
         "resolve-host",
         "network-state"
       ]
     }
 {% endif %}
-  ],
-
-{% if webapp_type == 'v1' %}
-  "plugins": [
-    { "path": "remoting_host_plugin.dll", "public": false },
-    { "path": "libremoting_host_plugin.ia32.so", "public": false },
-    { "path": "libremoting_host_plugin.x64.so", "public": false },
-    { "path": "remoting_host_plugin.plugin", "public": false }
-  ],
-  "requirements": {
-    "plugins": {
-      "npapi": false
-    }
-  }
-{% else %}
-  "oauth2": {
-    "client_id": "{{ REMOTING_IDENTITY_API_CLIENT_ID }}",
-    "scopes": [
-      "https://www.googleapis.com/auth/chromoting https://www.googleapis.com/auth/googletalk https://www.googleapis.com/auth/userinfo#email"
-    ]
-  },
-  "sandbox": {
-    "pages": [ "wcs_sandbox.html" ]
-  }
-{% endif %}
-
+  ]
 }