diff --git a/platform/chromium/managed_storage.json b/platform/chromium/managed_storage.json
index d3f2c864f9adf..44737cfbde8ae 100644
--- a/platform/chromium/managed_storage.json
+++ b/platform/chromium/managed_storage.json
@@ -3,9 +3,17 @@
   "type": "object",
   "properties": {
     "adminSettings": {
-      "title": "A valid JSON string compliant with uBO's backup format.",
+      "title": "A valid JSON string compliant with uBO's backup format",
       "description": "All entries present will overwrite local settings.",
       "type": "string"
+    },
+    "extraTrustedSiteDirectives": {
+      "title": "A list of trusted-site directives",
+      "description": "Trusted-site directives to always add at launch time.",
+      "type": "array",
+      "items": {
+        "type": "string"
+      }
     }
   }
 }
diff --git a/platform/chromium/vapi-background.js b/platform/chromium/vapi-background.js
index 9a5f4f0b3913d..871de996b601c 100644
--- a/platform/chromium/vapi-background.js
+++ b/platform/chromium/vapi-background.js
@@ -1417,13 +1417,13 @@ vAPI.commands = browser.commands;
 vAPI.adminStorage = (( ) => {
     if ( webext.storage.managed instanceof Object === false ) {
         return {
-            getItem: function() {
+            get: function() {
                 return Promise.resolve();
             },
         };
     }
     return {
-        getItem: async function(key) {
+        get: async function(key) {
             let bin;
             try {
                 bin = await webext.storage.managed.get(key);
diff --git a/src/js/start.js b/src/js/start.js
index 79a1a441a9a1d..d814750baac3b 100644
--- a/src/js/start.js
+++ b/src/js/start.js
@@ -133,11 +133,24 @@ const onVersionReady = function(lastVersion) {
 // Whitelist in memory.
 // Whitelist parser needs PSL to be ready.
 // gorhill 2014-12-15: not anymore
+//
+// https://github.com/uBlockOrigin/uBlock-issues/issues/1433
+//   Allow admins to add their own trusted-site directives.
 
-const onNetWhitelistReady = function(netWhitelistRaw) {
+const onNetWhitelistReady = function(netWhitelistRaw, adminExtra) {
     if ( typeof netWhitelistRaw === 'string' ) {
         netWhitelistRaw = netWhitelistRaw.split('\n');
     }
+    // Append admin-controlled trusted-site directives
+    if (
+        Array.isArray(adminExtra.trustedSites) &&
+        adminExtra.trustedSites.length !== 0
+    ) {
+        for ( const directive of adminExtra.trustedSites ) {
+            µb.netWhitelistDefault.push(directive);
+            netWhitelistRaw.push(directive);
+        }
+    }
     µb.netWhitelist = µb.whitelistFromArray(netWhitelistRaw);
     µb.netWhitelistModifyTime = Date.now();
 };
@@ -190,7 +203,7 @@ const onCacheSettingsReady = async function(fetched) {
 
 /******************************************************************************/
 
-const onFirstFetchReady = function(fetched) {
+const onFirstFetchReady = function(fetched, adminExtra) {
     // https://github.com/uBlockOrigin/uBlock-issues/issues/507
     //   Firefox-specific: somehow `fetched` is undefined under certain
     //   circumstances even though we asked to load with default values.
@@ -202,7 +215,7 @@ const onFirstFetchReady = function(fetched) {
     fromFetch(µb.localSettings, fetched);
     onUserSettingsReady(fetched);
     fromFetch(µb.restoreBackupSettings, fetched);
-    onNetWhitelistReady(fetched.netWhitelist);
+    onNetWhitelistReady(fetched.netWhitelist, adminExtra);
     onVersionReady(fetched.version);
 };
 
@@ -283,6 +296,11 @@ try {
     );
     log.info(`Backend storage for cache will be ${cacheBackend}`);
 
+    const adminExtra = {};
+    adminExtra.trustedSites =
+        await vAPI.adminStorage.get('extraTrustedSiteDirectives') || [];
+    log.info(`Extra admin settings ready ${Date.now()-vAPI.T0} ms after launch`);
+
     // https://github.com/uBlockOrigin/uBlock-issues/issues/1365
     //   Wait for onCacheSettingsReady() to be fully ready.
     await Promise.all([
@@ -297,7 +315,7 @@ try {
         }),
         vAPI.storage.get(createDefaultProps()).then(fetched => {
             log.info(`First fetch ready ${Date.now()-vAPI.T0} ms after launch`);
-            onFirstFetchReady(fetched);
+            onFirstFetchReady(fetched, adminExtra);
         }),
         µb.loadPublicSuffixList().then(( ) => {
             log.info(`PSL ready ${Date.now()-vAPI.T0} ms after launch`);
diff --git a/src/js/storage.js b/src/js/storage.js
index e86d02cd9b378..f22a729662244 100644
--- a/src/js/storage.js
+++ b/src/js/storage.js
@@ -1224,7 +1224,7 @@ self.addEventListener('hiddenSettingsChanged', ( ) => {
 µBlock.restoreAdminSettings = async function() {
     let data;
     try {
-        const json = await vAPI.adminStorage.getItem('adminSettings');
+        const json = await vAPI.adminStorage.get('adminSettings');
         if ( typeof json === 'string' && json !== '' ) {
             data = JSON.parse(json);
         } else if ( json instanceof Object ) {
diff --git a/src/js/whitelist.js b/src/js/whitelist.js
index 0ff38cd10d2e3..afd07bec855d2 100644
--- a/src/js/whitelist.js
+++ b/src/js/whitelist.js
@@ -70,7 +70,13 @@ CodeMirror.defineMode("ubo-whitelist-directives", function() {
                 }
                 return null;
             }
-            return reHostnameExtractor.test(line) ? null : 'error';
+            if ( reHostnameExtractor.test(line) === false ) {
+                return 'error';
+            }
+            if ( whitelistDefaultSet.has(line.trim()) ) {
+                return 'keyword';
+            }
+            return null;
         }
     };
 });