diff --git a/desktop/app/src/Client.tsx b/desktop/app/src/Client.tsx
index 20dfb92b9..8ea15b399 100644
--- a/desktop/app/src/Client.tsx
+++ b/desktop/app/src/Client.tsx
@@ -15,9 +15,7 @@ import {Payload, ConnectionStatus} from 'rsocket-types';
 import {Flowable, Single} from 'rsocket-flowable';
 import {performance} from 'perf_hooks';
 import {reportPluginFailures} from './utils/metrics';
-import {notNull} from './utils/typeUtils';
 import {default as isProduction} from './utils/isProduction';
-import {registerPlugins} from './reducers/plugins';
 import {EventEmitter} from 'events';
 import invariant from 'invariant';
 import {
@@ -39,7 +37,8 @@ import {freeze} from 'immer';
 import GK from './fb-stubs/GK';
 import {message} from 'antd';
 
-type Plugins = Array<string>;
+type Plugins = Set<string>;
+type PluginsArr = Array<string>;
 
 export type ClientQuery = {
   app: string;
@@ -149,8 +148,8 @@ export default class Client extends EventEmitter {
   ) {
     super();
     this.connected.set(!!conn);
-    this.plugins = plugins ? plugins : [];
-    this.backgroundPlugins = [];
+    this.plugins = plugins ? plugins : new Set();
+    this.backgroundPlugins = new Set();
     this.connection = conn;
     this.id = id;
     this.query = query;
@@ -184,11 +183,11 @@ export default class Client extends EventEmitter {
   }
 
   supportsPlugin(pluginId: string): boolean {
-    return this.plugins.includes(pluginId);
+    return this.plugins.has(pluginId);
   }
 
   isBackgroundPlugin(pluginId: string) {
-    return this.backgroundPlugins.includes(pluginId);
+    return this.backgroundPlugins.has(pluginId);
   }
 
   isEnabledPlugin(pluginId: string) {
@@ -210,7 +209,7 @@ export default class Client extends EventEmitter {
     this.plugins.forEach((pluginId) =>
       this.startPluginIfNeeded(this.getPlugin(pluginId)),
     );
-    this.backgroundPlugins = await this.getBackgroundPlugins();
+    this.backgroundPlugins = new Set(await this.getBackgroundPlugins());
     this.backgroundPlugins.forEach((plugin) => {
       if (this.shouldConnectAsBackgroundPlugin(plugin)) {
         this.initPlugin(plugin);
@@ -244,7 +243,7 @@ export default class Client extends EventEmitter {
       'getPlugins',
       false,
     );
-    this.plugins = plugins;
+    this.plugins = new Set(plugins);
     return plugins;
   }
 
@@ -313,13 +312,14 @@ export default class Client extends EventEmitter {
   }
 
   // get the supported background plugins
-  async getBackgroundPlugins(): Promise<Plugins> {
+  async getBackgroundPlugins(): Promise<PluginsArr> {
     if (this.sdkVersion < 4) {
       return [];
     }
-    return this.rawCall<{plugins: Plugins}>('getBackgroundPlugins', false).then(
-      (data) => data.plugins,
-    );
+    return this.rawCall<{plugins: PluginsArr}>(
+      'getBackgroundPlugins',
+      false,
+    ).then((data) => data.plugins);
   }
 
   // get the plugins, and update the UI
@@ -330,11 +330,11 @@ export default class Client extends EventEmitter {
       this.startPluginIfNeeded(this.getPlugin(pluginId)),
     );
     const newBackgroundPlugins = await this.getBackgroundPlugins();
-    this.backgroundPlugins = newBackgroundPlugins;
+    this.backgroundPlugins = new Set(newBackgroundPlugins);
     // diff the background plugin list, disconnect old, connect new ones
     oldBackgroundPlugins.forEach((plugin) => {
       if (
-        !newBackgroundPlugins.includes(plugin) &&
+        !this.backgroundPlugins.has(plugin) &&
         this.store
           .getState()
           .connections.enabledPlugins[this.query.app]?.includes(plugin)
@@ -344,7 +344,7 @@ export default class Client extends EventEmitter {
     });
     newBackgroundPlugins.forEach((plugin) => {
       if (
-        !oldBackgroundPlugins.includes(plugin) &&
+        !oldBackgroundPlugins.has(plugin) &&
         this.shouldConnectAsBackgroundPlugin(plugin)
       ) {
         this.initPlugin(plugin);
diff --git a/desktop/app/src/PluginContainer.tsx b/desktop/app/src/PluginContainer.tsx
index b38956dee..b6f9cec74 100644
--- a/desktop/app/src/PluginContainer.tsx
+++ b/desktop/app/src/PluginContainer.tsx
@@ -417,10 +417,7 @@ class PluginContainer extends PureComponent<Props, State> {
         selectPlugin: (pluginID: string, deepLinkPayload: unknown) => {
           const {target} = this.props;
           // check if plugin will be available
-          if (
-            target instanceof Client &&
-            target.plugins.some((p) => p === pluginID)
-          ) {
+          if (target instanceof Client && target.plugins.has(pluginID)) {
             this.props.selectPlugin({
               selectedPlugin: pluginID,
               deepLinkPayload,
diff --git a/desktop/app/src/__tests__/createMockFlipperWithPlugin.node.tsx b/desktop/app/src/__tests__/createMockFlipperWithPlugin.node.tsx
index 1b845e319..02f935c59 100644
--- a/desktop/app/src/__tests__/createMockFlipperWithPlugin.node.tsx
+++ b/desktop/app/src/__tests__/createMockFlipperWithPlugin.node.tsx
@@ -47,7 +47,7 @@ test('can create a Fake flipper', async () => {
   expect(device).toBeTruthy();
   expect(store).toBeTruthy();
   expect(sendMessage).toBeTruthy();
-  expect(client.plugins.includes(TestPlugin.id)).toBe(true);
+  expect(client.plugins.has(TestPlugin.id)).toBe(true);
   expect(store.getState().connections).toMatchSnapshot();
   expect(store.getState().plugins).toMatchSnapshot();
   sendMessage('inc', {});
@@ -73,7 +73,7 @@ test('can create a Fake flipper with legacy wrapper', async () => {
   expect(device).toBeTruthy();
   expect(store).toBeTruthy();
   expect(sendMessage).toBeTruthy();
-  expect(client.plugins.includes(TestPlugin.id)).toBe(true);
+  expect(client.plugins.has(TestPlugin.id)).toBe(true);
   expect(client.sandyPluginStates.has(TestPlugin.id)).toBe(true);
   const state = store.getState();
   expect(state.connections).toMatchSnapshot();
diff --git a/desktop/app/src/chrome/plugin-manager/PluginDebugger.tsx b/desktop/app/src/chrome/plugin-manager/PluginDebugger.tsx
index 8c8e5b6d6..d9015c07b 100644
--- a/desktop/app/src/chrome/plugin-manager/PluginDebugger.tsx
+++ b/desktop/app/src/chrome/plugin-manager/PluginDebugger.tsx
@@ -128,7 +128,7 @@ class PluginDebugger extends Component<Props> {
   getSupportedClients(id: string): string {
     return this.props.clients
       .reduce((acc: Array<string>, cv: Client) => {
-        if (cv.plugins.includes(id)) {
+        if (cv.plugins.has(id)) {
           acc.push(cv.query.app);
         }
         return acc;
diff --git a/desktop/app/src/reducers/supportForm.tsx b/desktop/app/src/reducers/supportForm.tsx
index fdd6e27ee..80ede5bdb 100644
--- a/desktop/app/src/reducers/supportForm.tsx
+++ b/desktop/app/src/reducers/supportForm.tsx
@@ -132,7 +132,7 @@ export class Group {
           enabledPlugins != null && enabledPlugins.includes(requiredPlugin);
         if (
           selectedClient &&
-          selectedClient.plugins.includes(requiredPlugin) &&
+          selectedClient.plugins.has(requiredPlugin) &&
           !requiredPluginEnabled
         ) {
           const plugin =
@@ -146,7 +146,7 @@ export class Group {
           );
         } else if (
           !selectedClient ||
-          !selectedClient.plugins.includes(requiredPlugin)
+          !selectedClient.plugins.has(requiredPlugin)
         ) {
           unsupportedPlugins.push(requiredPlugin);
         }
diff --git a/desktop/app/src/sandy-chrome/appinspect/__tests__/PluginList.spec.tsx b/desktop/app/src/sandy-chrome/appinspect/__tests__/PluginList.spec.tsx
index e02fa43a0..7c990b94c 100644
--- a/desktop/app/src/sandy-chrome/appinspect/__tests__/PluginList.spec.tsx
+++ b/desktop/app/src/sandy-chrome/appinspect/__tests__/PluginList.spec.tsx
@@ -224,11 +224,11 @@ describe('basic findBestDevice with metro present', () => {
     );
 
     // ok, this is a little hackish
-    flipper.client.plugins = [
+    flipper.client.plugins = new Set([
       'plugin1',
       'plugin2',
       'supportedUninstalledPlugin',
-    ];
+    ]);
 
     let state = flipper.store.getState();
     const pluginLists = computePluginLists(state.connections, state.plugins);
diff --git a/desktop/app/src/server.tsx b/desktop/app/src/server.tsx
index 92f9e9375..57f081c4b 100644
--- a/desktop/app/src/server.tsx
+++ b/desktop/app/src/server.tsx
@@ -555,9 +555,9 @@ class Server extends EventEmitter {
 
       client.init().then(() => {
         console.debug(
-          `Device client initialised: ${id}. Supported plugins: ${client.plugins.join(
-            ', ',
-          )}`,
+          `Device client initialised: ${id}. Supported plugins: ${Array.from(
+            client.plugins,
+          ).join(', ')}`,
           'server',
         );
 
diff --git a/desktop/app/src/test-utils/MockFlipper.tsx b/desktop/app/src/test-utils/MockFlipper.tsx
index 3b76b089a..d8e48e864 100644
--- a/desktop/app/src/test-utils/MockFlipper.tsx
+++ b/desktop/app/src/test-utils/MockFlipper.tsx
@@ -181,7 +181,7 @@ export default class MockFlipper {
       device.isArchived ? null : createStubConnection(),
       this._logger,
       this._store,
-      supportedPlugins,
+      new Set(supportedPlugins),
       device,
     );
     // yikes
diff --git a/desktop/app/src/utils/__tests__/exportData.node.tsx b/desktop/app/src/utils/__tests__/exportData.node.tsx
index 4219a4944..1ae5a803a 100644
--- a/desktop/app/src/utils/__tests__/exportData.node.tsx
+++ b/desktop/app/src/utils/__tests__/exportData.node.tsx
@@ -718,7 +718,7 @@ test('test determinePluginsToProcess for mutilple clients having plugins present
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     device1,
   );
   const client2 = new Client(
@@ -732,7 +732,7 @@ test('test determinePluginsToProcess for mutilple clients having plugins present
     null,
     logger,
     mockStore,
-    ['TestDevicePlugin'],
+    new Set(['TestDevicePlugin']),
     device1,
   );
   const client3 = new Client(
@@ -746,7 +746,7 @@ test('test determinePluginsToProcess for mutilple clients having plugins present
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     device1,
   );
   const plugins: PluginsState = {
@@ -807,7 +807,7 @@ test('test determinePluginsToProcess for no selected plugin present in any clien
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     device1,
   );
   const client2 = new Client(
@@ -821,7 +821,7 @@ test('test determinePluginsToProcess for no selected plugin present in any clien
     null,
     logger,
     mockStore,
-    ['TestDevicePlugin'],
+    new Set(['TestDevicePlugin']),
     device1,
   );
   const plugins: PluginsState = {
@@ -863,7 +863,7 @@ test('test determinePluginsToProcess for multiple clients on same device', async
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     device1,
   );
   const client2 = new Client(
@@ -877,7 +877,7 @@ test('test determinePluginsToProcess for multiple clients on same device', async
     null,
     logger,
     mockStore,
-    ['TestDevicePlugin'],
+    new Set(['TestDevicePlugin']),
     device1,
   );
   const plugins: PluginsState = {
@@ -925,7 +925,7 @@ test('test determinePluginsToProcess for multiple clients on different device',
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     device1,
   );
   const client2Device1 = new Client(
@@ -939,7 +939,7 @@ test('test determinePluginsToProcess for multiple clients on different device',
     null,
     logger,
     mockStore,
-    ['TestDevicePlugin'],
+    new Set(['TestDevicePlugin']),
     device1,
   );
   const client1Device2 = new Client(
@@ -953,7 +953,7 @@ test('test determinePluginsToProcess for multiple clients on different device',
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     device1,
   );
   const client2Device2 = new Client(
@@ -967,7 +967,7 @@ test('test determinePluginsToProcess for multiple clients on different device',
     null,
     logger,
     mockStore,
-    ['TestDevicePlugin'],
+    new Set(['TestDevicePlugin']),
     device1,
   );
   const plugins: PluginsState = {
@@ -1039,7 +1039,7 @@ test('test determinePluginsToProcess to ignore archived clients', async () => {
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     archivedDevice,
   );
   const archivedClient = new Client(
@@ -1053,7 +1053,7 @@ test('test determinePluginsToProcess to ignore archived clients', async () => {
     null,
     logger,
     mockStore,
-    ['TestPlugin', 'TestDevicePlugin'],
+    new Set(['TestPlugin', 'TestDevicePlugin']),
     archivedDevice,
   );
   const plugins: PluginsState = {
@@ -1303,7 +1303,7 @@ test('Sandy plugins are imported properly', async () => {
   const client2 = store.getState().connections.clients[1];
   expect(client2).not.toBeFalsy();
   expect(client2).not.toBe(client);
-  expect(client2.plugins).toEqual([TestPlugin.id]);
+  expect(Array.from(client2.plugins)).toEqual([TestPlugin.id]);
 
   expect(client.sandyPluginStates.get(TestPlugin.id)!.exportStateSync())
     .toMatchInlineSnapshot(`
diff --git a/desktop/app/src/utils/exportData.tsx b/desktop/app/src/utils/exportData.tsx
index 8f5156f52..1f503db2e 100644
--- a/desktop/app/src/utils/exportData.tsx
+++ b/desktop/app/src/utils/exportData.tsx
@@ -619,11 +619,13 @@ export function determinePluginsToProcess(
     }
     const selectedFilteredPlugins = client
       ? selectedPlugins.length > 0
-        ? client.plugins.filter((plugin) => selectedPlugins.includes(plugin))
+        ? Array.from(client.plugins).filter((plugin) =>
+            selectedPlugins.includes(plugin),
+          )
         : client.plugins
       : [];
     for (const plugin of selectedFilteredPlugins) {
-      if (!client.plugins.includes(plugin)) {
+      if (!client.plugins.has(plugin)) {
         // Ignore clients which doesn't support the selected plugins.
         continue;
       }
@@ -827,7 +829,7 @@ export function importDataToStore(source: string, data: string, store: Store) {
 
   clients.forEach((client: {id: string; query: ClientQuery}) => {
     const sandyPluginStates = json.pluginStates2[client.id] || {};
-    const clientPlugins: Array<string> = [
+    const clientPlugins: Set<string> = new Set([
       ...keys
         .filter((key) => {
           const plugin = deconstructPluginKey(key);
@@ -835,7 +837,7 @@ export function importDataToStore(source: string, data: string, store: Store) {
         })
         .map((pluginKey) => deconstructPluginKey(pluginKey).pluginName),
       ...Object.keys(sandyPluginStates),
-    ];
+    ]);
     store.dispatch({
       type: 'NEW_CLIENT',
       payload: new Client(
diff --git a/desktop/app/src/utils/pluginUtils.tsx b/desktop/app/src/utils/pluginUtils.tsx
index b4eacbfa4..48c41736f 100644
--- a/desktop/app/src/utils/pluginUtils.tsx
+++ b/desktop/app/src/utils/pluginUtils.tsx
@@ -352,9 +352,7 @@ function getFavoritePlugins(
       return [];
     }
     // for *imported* devices, all stored plugins are enabled
-    return allPlugins.filter(
-      (plugin) => client.plugins.indexOf(plugin.id) !== -1,
-    );
+    return allPlugins.filter((plugin) => client.plugins.has(plugin.id));
   }
   if (!enabledPlugins || !enabledPlugins.length) {
     return returnFavoredPlugins ? [] : allPlugins;
diff --git a/desktop/app/tsconfig.json b/desktop/app/tsconfig.json
index ca8ea7e67..f49ae1151 100644
--- a/desktop/app/tsconfig.json
+++ b/desktop/app/tsconfig.json
@@ -27,6 +27,5 @@
     "**/node_modules/",
     "**/__tests__/",
     "**/lib/",
-    "**/fb/"
   ]
 }
diff --git a/desktop/flipper-plugin/src/plugin/Plugin.tsx b/desktop/flipper-plugin/src/plugin/Plugin.tsx
index c1003918b..07ad1a36e 100644
--- a/desktop/flipper-plugin/src/plugin/Plugin.tsx
+++ b/desktop/flipper-plugin/src/plugin/Plugin.tsx
@@ -108,7 +108,7 @@ export interface RealFlipperClient {
     device_id: string;
   };
   deviceSync: RealFlipperDevice;
-  plugins: string[];
+  plugins: Set<string>;
   isBackgroundPlugin(pluginId: string): boolean;
   initPlugin(pluginId: string): void;
   deinitPlugin(pluginId: string): void;
diff --git a/desktop/flipper-plugin/src/test-utils/test-utils.tsx b/desktop/flipper-plugin/src/test-utils/test-utils.tsx
index df9968289..ab28d76de 100644
--- a/desktop/flipper-plugin/src/test-utils/test-utils.tsx
+++ b/desktop/flipper-plugin/src/test-utils/test-utils.tsx
@@ -196,7 +196,7 @@ export function startPlugin<Module extends FlipperPluginModule<any>>(
   const deviceName = 'TestDevice';
   const fakeFlipperClient: RealFlipperClient = {
     id: `${appName}#${testDevice.os}#${deviceName}#${testDevice.serial}`,
-    plugins: [definition.id],
+    plugins: new Set([definition.id]),
     query: {
       app: appName,
       device: deviceName,