--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -7159,54 +7159,49 @@ var gIdentityHandler = {
   },
 
   updateSitePermissions: function () {
     while (this._permissionList.hasChildNodes())
       this._permissionList.removeChild(this._permissionList.lastChild);
 
     let uri = gBrowser.currentURI;
 
-    for (let permission of SitePermissions.listPermissions()) {
-      let state = SitePermissions.get(uri, permission);
-
-      if (state == SitePermissions.UNKNOWN)
-        continue;
-
-      let item = this._createPermissionItem(permission, state);
+    for (let permission of SitePermissions.getPermissionsByURI(uri)) {
+      let item = this._createPermissionItem(permission);
       this._permissionList.appendChild(item);
     }
   },
 
   setPermission: function (aPermission, aState) {
     if (aState == SitePermissions.getDefault(aPermission))
       SitePermissions.remove(gBrowser.currentURI, aPermission);
     else
       SitePermissions.set(gBrowser.currentURI, aPermission, aState);
   },
 
-  _createPermissionItem: function (aPermission, aState) {
+  _createPermissionItem: function (aPermission) {
     let menulist = document.createElement("menulist");
     let menupopup = document.createElement("menupopup");
-    for (let state of SitePermissions.getAvailableStates(aPermission)) {
+    for (let state of aPermission.availableStates) {
       let menuitem = document.createElement("menuitem");
-      menuitem.setAttribute("value", state);
-      menuitem.setAttribute("label", SitePermissions.getStateLabel(aPermission, state));
+      menuitem.setAttribute("value", state.id);
+      menuitem.setAttribute("label", state.label);
       menupopup.appendChild(menuitem);
     }
     menulist.appendChild(menupopup);
-    menulist.setAttribute("value", aState);
+    menulist.setAttribute("value", aPermission.state);
     menulist.setAttribute("oncommand", "gIdentityHandler.setPermission('" +
-                                       aPermission + "', this.value)");
-    menulist.setAttribute("id", "identity-popup-permission:" + aPermission);
+                                       aPermission.id + "', this.value)");
+    menulist.setAttribute("id", "identity-popup-permission:" + aPermission.id);
 
     let label = document.createElement("label");
     label.setAttribute("flex", "1");
     label.setAttribute("class", "identity-popup-permission-label");
     label.setAttribute("control", menulist.getAttribute("id"));
-    label.textContent = SitePermissions.getPermissionLabel(aPermission);
+    label.textContent = aPermission.label;
 
     let container = document.createElement("hbox");
     container.setAttribute("align", "center");
     container.appendChild(label);
     container.appendChild(menulist);
 
     // The menuitem text can be long and we don't want the dropdown
     // to expand to the width of unselected labels.

--- a/browser/modules/SitePermissions.jsm
+++ b/browser/modules/SitePermissions.jsm
@@ -11,16 +11,55 @@ var gStringBundle =
 
 this.SitePermissions = {
 
   UNKNOWN: Services.perms.UNKNOWN_ACTION,
   ALLOW: Services.perms.ALLOW_ACTION,
   BLOCK: Services.perms.DENY_ACTION,
   SESSION: Components.interfaces.nsICookiePermission.ACCESS_SESSION,
 
+  /* Returns a list of objects representing all permissions that are currently
+   * set for the given URI. Each object contains the following keys:
+   * - id: the permissionID of the permission
+   * - label: the localized label
+   * - state: a constant representing the current permission state
+   *   (e.g. SitePermissions.ALLOW)
+   * - availableStates: an array of all available states for that permission,
+   *   represented as objects with the keys:
+   *   - id: the state constant
+   *   - label: the translated label of that state
+   */
+  getPermissionsByURI: function (aURI) {
+    if (!this.isSupportedURI(aURI)) {
+      return [];
+    }
+
+    let permissions = [];
+    for (let permission of this.listPermissions()) {
+      let state = this.get(aURI, permission);
+      if (state === this.UNKNOWN) {
+        continue;
+      }
+
+      let availableStates = this.getAvailableStates(permission).map( state => {
+        return { id: state, label: this.getStateLabel(permission, state) };
+      });
+      let label = this.getPermissionLabel(permission);
+
+      permissions.push({
+        id: permission,
+        label: label,
+        state: state,
+        availableStates: availableStates,
+      });
+    }
+
+    return permissions;
+  },
+
   /* Returns a boolean indicating whether there are any granted
    * (meaning allowed or session-allowed) permissions for the given URI.
    * Will return false for invalid URIs (such as file:// URLs).
    */
   hasGrantedPermissions: function (aURI) {
     if (!this.isSupportedURI(aURI)) {
       return false;
     }

--- a/browser/modules/test/xpcshell/test_SitePermissions.js
+++ b/browser/modules/test/xpcshell/test_SitePermissions.js
@@ -9,16 +9,21 @@ Components.utils.import("resource://gre/
 add_task(function* testPermissionsListing() {
   Assert.deepEqual(SitePermissions.listPermissions().sort(),
     ["camera","cookie","desktop-notification","geo","image",
      "indexedDB","install","microphone","pointerLock","popup"],
     "Correct list of all permissions");
 });
 
 add_task(function* testHasGrantedPermissions() {
+  // check that it returns false on an invalid URI
+  // like a file URI, which doesn't support site permissions
+  let wrongURI = Services.io.newURI("file:///example.js", null, null)
+  Assert.equal(SitePermissions.hasGrantedPermissions(wrongURI), false);
+
   let uri = Services.io.newURI("https://example.com", null, null)
   Assert.equal(SitePermissions.hasGrantedPermissions(uri), false);
 
   // check that ALLOW states return true
   SitePermissions.set(uri, "camera", SitePermissions.ALLOW);
   Assert.equal(SitePermissions.hasGrantedPermissions(uri), true);
 
   // removing the ALLOW state should revert to false
@@ -44,8 +49,70 @@ add_task(function* testHasGrantedPermiss
   Assert.equal(SitePermissions.hasGrantedPermissions(uri), true);
 
   // check that only BLOCK states will not return true
   SitePermissions.remove(uri, "geo");
   Assert.equal(SitePermissions.hasGrantedPermissions(uri), false);
 
   SitePermissions.remove(uri, "pointerLock");
 });
+
+add_task(function* testGetPermissionsByURI() {
+  // check that it returns an empty array on an invalid URI
+  // like a file URI, which doesn't support site permissions
+  let wrongURI = Services.io.newURI("file:///example.js", null, null)
+  Assert.deepEqual(SitePermissions.getPermissionsByURI(wrongURI), []);
+
+  let uri = Services.io.newURI("https://example.com", null, null)
+
+  SitePermissions.set(uri, "camera", SitePermissions.ALLOW);
+  SitePermissions.set(uri, "cookie", SitePermissions.SESSION);
+  SitePermissions.set(uri, "popup", SitePermissions.BLOCK);
+
+  let permissions = SitePermissions.getPermissionsByURI(uri);
+
+  let camera = permissions.find(({id}) => id === "camera");
+  Assert.deepEqual(camera, {
+    id: "camera",
+    label: "Use the Camera",
+    state: SitePermissions.ALLOW,
+    availableStates: [
+      { id: SitePermissions.UNKNOWN, label: "Always Ask" },
+      { id: SitePermissions.ALLOW, label: "Allow" },
+      { id: SitePermissions.BLOCK, label: "Block" },
+    ]
+  });
+
+  // check that removed permissions (State.UNKNOWN) are skipped
+  SitePermissions.remove(uri, "camera");
+  permissions = SitePermissions.getPermissionsByURI(uri);
+
+  camera = permissions.find(({id}) => id === "camera");
+  Assert.equal(camera, undefined);
+
+  // check that different available state values are represented
+
+  let cookie = permissions.find(({id}) => id === "cookie");
+  Assert.deepEqual(cookie, {
+    id: "cookie",
+    label: "Set Cookies",
+    state: SitePermissions.SESSION,
+    availableStates: [
+      { id: SitePermissions.ALLOW, label: "Allow" },
+      { id: SitePermissions.SESSION, label: "Allow for Session" },
+      { id: SitePermissions.BLOCK, label: "Block" },
+    ]
+  });
+
+  let popup = permissions.find(({id}) => id === "popup");
+  Assert.deepEqual(popup, {
+    id: "popup",
+    label: "Open Pop-up Windows",
+    state: SitePermissions.BLOCK,
+    availableStates: [
+      { id: SitePermissions.ALLOW, label: "Allow" },
+      { id: SitePermissions.BLOCK, label: "Block" },
+    ]
+  });
+
+  SitePermissions.remove(uri, "cookie");
+  SitePermissions.remove(uri, "popup");
+});