diff --git a/packages/app-clipper/manifest.json b/packages/app-clipper/manifest.json
index de28de395..f182d4ea9 100644
--- a/packages/app-clipper/manifest.json
+++ b/packages/app-clipper/manifest.json
@@ -1,7 +1,7 @@
 {
     "manifest_version": 2,
     "name": "Joplin Web Clipper [DEV]",
-    "version": "2.1.1",
+    "version": "2.1.2",
     "description": "Capture and save web pages and screenshots from your browser to Joplin.",
     "homepage_url": "https://joplinapp.org",
     "content_security_policy": "script-src 'self'; object-src 'self'",
diff --git a/packages/app-clipper/popup/src/App.js b/packages/app-clipper/popup/src/App.js
index 3b5b5c4c3..236feb127 100644
--- a/packages/app-clipper/popup/src/App.js
+++ b/packages/app-clipper/popup/src/App.js
@@ -237,12 +237,18 @@ class AppComponent extends Component {
 	renderStartupScreen() {
 		const messages = {
 			serverFoundState: {
+				// We need to display the "Connecting to the Joplin
+				// application..." message because if the app doesn't currently
+				// allow access to the clipper API, the clipper tries several
+				// ports and it takes time before failing. So if we don't
+				// display any message, it looks like it's not doing anything
+				// when clicking on the extension button.
 				'searching': 'Connecting to the Joplin application...',
 				'not_found': 'Error: Could not connect to the Joplin application. Please ensure that it is started and that the clipper service is enabled in the configuration.',
 			},
 			authState: {
 				'starting': 'Starting...',
-				'waiting': 'The Joplin Web Clipper requires your authorisation in order to access your data. To do, please open the Joplin desktop application and grant permission. Note: Joplin 2.1+ is needed to use this version of the Web Clipper.',
+				'waiting': 'The Joplin Web Clipper requires your authorisation in order to access your data. To proceed, please open the Joplin desktop application and grant permission. Note: Joplin 2.1+ is needed to use this version of the Web Clipper.',
 				'rejected': 'Permission to access your data was not granted. To try again please close this popup and open it again.',
 			},
 		};
diff --git a/packages/app-clipper/popup/src/bridge.js b/packages/app-clipper/popup/src/bridge.js
index 4ff6c4059..1d4912490 100644
--- a/packages/app-clipper/popup/src/bridge.js
+++ b/packages/app-clipper/popup/src/bridge.js
@@ -85,7 +85,13 @@ class Bridge {
 			type: 'ENV_SET',
 			env: this.env(),
 		});
+	}
 
+	token() {
+		return this.token_;
+	}
+
+	async onReactAppStarts() {
 		await this.findClipperServerPort();
 
 		if (this.clipperServerPortStatus_ !== 'found') {
@@ -94,13 +100,7 @@ class Bridge {
 		}
 
 		await this.restoreState();
-	}
 
-	token() {
-		return this.token_;
-	}
-
-	async onReactAppStarts() {
 		await this.checkAuth();
 		if (!this.token_) return; // Didn't get a token
 
@@ -138,29 +138,59 @@ class Bridge {
 
 		this.dispatch({ type: 'AUTH_STATE_SET', value: 'waiting' });
 
-		const response = await this.clipperApiExec('POST', 'auth');
-		const authToken = response.auth_token;
+		// Note that Firefox and Chrome works differently for this:
+		//
+		// - In Chrome, the popup stays open, even when the user leaves the
+		//   browser to grant permission in the application.
+		//
+		// - In Firefox, as soon as the browser loses focus, the popup closes.
+		//
+		//   It means we can't rely on local state to get this working - instead
+		//   we request the auth token, and cache it to local storage (along
+		//   with a timestamp). Then next time the user opens the popup (after
+		//   it was automatically closed by Firefox), that cached auth token is
+		//   re-used and the auth process continues.
+		//
+		// https://github.com/laurent22/joplin/issues/5125#issuecomment-869547421
+
+		const existingAuthInfo = await this.storageGet(['authToken', 'authTokenTimestamp']);
+
+		let authToken = null;
+		if (existingAuthInfo.authToken && Date.now() - existingAuthInfo.authTokenTimestamp < 5 * 60 * 1000) {
+			console.info('checkAuth: we already have an auth token - reusing it');
+			authToken = existingAuthInfo.authToken;
+		} else {
+			console.info('checkAuth: we do not have an auth token - requesting it...');
+			const response = await this.clipperApiExec('POST', 'auth');
+			authToken = response.auth_token;
+
+			await this.storageSet({ authToken: authToken, authTokenTimestamp: Date.now() });
+		}
 
 		console.info('checkAuth: we do not have a token - requesting one using auth_token: ', authToken);
 
-		while (true) {
-			const response = await this.clipperApiExec('GET', 'auth/check', { auth_token: authToken });
+		try {
+			while (true) {
+				const response = await this.clipperApiExec('GET', 'auth/check', { auth_token: authToken });
 
-			if (response.status === 'rejected') {
-				console.info('checkAuth: Auth request was not accepted', response);
-				this.dispatch({ type: 'AUTH_STATE_SET', value: 'rejected' });
-				break;
-			} else if (response.status === 'accepted') {
-				console.info('checkAuth: Auth request was accepted', response);
-				this.dispatch({ type: 'AUTH_STATE_SET', value: 'accepted' });
-				this.token_ = response.token;
-				await this.storageSet({ token: this.token_ });
-				break;
-			} else if (response.status === 'waiting') {
-				await msleep(1000);
-			} else {
-				throw new Error(`Unknown auth/check status: ${response.status}`);
+				if (response.status === 'rejected') {
+					console.info('checkAuth: Auth request was not accepted', response);
+					this.dispatch({ type: 'AUTH_STATE_SET', value: 'rejected' });
+					break;
+				} else if (response.status === 'accepted') {
+					console.info('checkAuth: Auth request was accepted', response);
+					this.dispatch({ type: 'AUTH_STATE_SET', value: 'accepted' });
+					this.token_ = response.token;
+					await this.storageSet({ token: this.token_ });
+					break;
+				} else if (response.status === 'waiting') {
+					await msleep(1000);
+				} else {
+					throw new Error(`Unknown auth/check status: ${response.status}`);
+				}
 			}
+		} finally {
+			await this.storageSet({ authToken: '', authTokenTimestamp: 0 });
 		}
 	}