diff --git a/.devcontainer/docker-compose.devcontainer.yaml b/.devcontainer/docker-compose.devcontainer.yaml
index ccaae78..d356c19 100644
--- a/.devcontainer/docker-compose.devcontainer.yaml
+++ b/.devcontainer/docker-compose.devcontainer.yaml
@@ -7,11 +7,12 @@ services:
     volumes:
       - ..:/workspace
     environment:
-      DISPLAY: novnc:0.0
+      DISPLAY: ${DISPLAY:-novnc:0.0}
     healthcheck:
       disable: true
     cap_add:
       - SYS_ADMIN
+    shm_size: 2gb
 
   novnc:
     image: theasp/novnc:latest
diff --git a/src/components/Config.svelte b/src/components/Config.svelte
index 6cc5394..248c3e3 100644
--- a/src/components/Config.svelte
+++ b/src/components/Config.svelte
@@ -4,6 +4,7 @@
 	import P from 'flowbite-svelte/P.svelte';
 	import { get } from 'svelte/store';
 	import Eye from '~/components/Eye.svelte';
+	import { putMessage } from '~/lib/messages';
 	import { launchWebAuthFlow as _launchWebAuthFlow } from '~/lib/raindrop/auth';
 	import { accessToken, clientID, clientSecret, refreshToken } from '~/lib/settings';
 
@@ -20,9 +21,10 @@
 			});
 			accessToken.set(result.accessToken);
 			refreshToken.set(result.refreshToken);
+			putMessage({ type: 'success', message: 'Successfully authorized app.' });
 		} catch (err) {
-			// TODO: Show error message as modal or toast
 			console.error('Failed to authorize app:', err);
+			putMessage({ type: 'error', message: String(err) });
 		}
 	};
 </script>
@@ -80,7 +82,6 @@
 					classDiv="w-full mr-2"
 					id="access-token"
 					type={showAccessToken ? 'text' : 'password'}
-					disabled
 					bind:value={$accessToken}
 				>
 					Access Token
diff --git a/src/components/Config.test.ts b/src/components/Config.test.ts
index e24e5ba..e460e54 100644
--- a/src/components/Config.test.ts
+++ b/src/components/Config.test.ts
@@ -71,7 +71,7 @@ describe('access token', () => {
 		const { getByTestId } = render(Config);
 		const input = getByTestId('access-token/input') as HTMLInputElement;
 		expect(input).toBeTruthy();
-		expect(input.getAttributeNames()).toContain('disabled');
+		expect(input.getAttributeNames()).not.toContain('disabled');
 	});
 
 	it('is masked by default and able to toggle it', async () => {
diff --git a/src/components/Message.svelte b/src/components/Message.svelte
new file mode 100644
index 0000000..eaec8bc
--- /dev/null
+++ b/src/components/Message.svelte
@@ -0,0 +1,42 @@
+<script lang="ts">
+	import { Toast } from 'flowbite-svelte';
+	import {
+		CheckCircleSolid,
+		CloseCircleSolid,
+		ExclamationCircleSolid
+	} from 'flowbite-svelte-icons';
+	import type { ComponentType } from 'svelte';
+	import { dismissMessage, type Message } from '~/lib/messages';
+
+	const messageMapping: {
+		[type: string]: { icon: ComponentType; color: 'blue' | 'green' | 'red' };
+	} = {
+		success: {
+			icon: CheckCircleSolid,
+			color: 'green'
+		},
+		info: {
+			icon: ExclamationCircleSolid,
+			color: 'blue'
+		},
+		error: {
+			icon: CloseCircleSolid,
+			color: 'red'
+		}
+	};
+
+	export let message: Message;
+</script>
+
+{#if message}
+	{@const color = messageMapping[message.type].color}
+	{@const icon = messageMapping[message.type].icon}
+	<div {...$$restProps}>
+		<Toast {color} on:close={() => dismissMessage(message.id)}>
+			<svelte:fragment slot="icon">
+				<svelte:component this={icon} class="h-5 w-5" />
+			</svelte:fragment>
+			{message.message}
+		</Toast>
+	</div>
+{/if}
diff --git a/src/components/Message.test.ts b/src/components/Message.test.ts
new file mode 100644
index 0000000..28a3627
--- /dev/null
+++ b/src/components/Message.test.ts
@@ -0,0 +1,9 @@
+// @vitest-environment jsdom
+import { render } from '@testing-library/svelte';
+import { expect, it } from 'vitest';
+import Message from './Message.svelte';
+
+it('renders OK', () => {
+	const { container } = render(Message);
+	expect(container).toBeTruthy();
+});
diff --git a/src/lib/messages.ts b/src/lib/messages.ts
new file mode 100644
index 0000000..ed9e663
--- /dev/null
+++ b/src/lib/messages.ts
@@ -0,0 +1,48 @@
+import { writable } from 'svelte/store';
+
+export type Message = {
+	id?: string;
+	type: 'success' | 'info' | 'error';
+	message: string;
+};
+
+export type MessageBox = {
+	[id: string]: Message;
+};
+
+export const messageBox = writable<MessageBox>({});
+
+/**
+ * Put message to message box.
+ * @param message Message to put. If `.id` is not set, random generated ID will be used.
+ * @returns ID of message.
+ */
+export function putMessage(message: Message): string {
+	const id = message.id ?? Math.random().toString(36).substring(2);
+	messageBox.update((box) => {
+		box[id] = { id, ...message };
+		return box;
+	});
+	return id;
+}
+
+/**
+ * Dismiss message with ID.
+ * @param id ID of message.
+ */
+export function dismissMessage(id?: string) {
+	if (!id) return;
+
+	messageBox.update((box) => {
+		delete box[id];
+		return box;
+	});
+}
+
+/* c8 ignore start */
+if (import.meta.vitest) {
+	const { describe } = import.meta.vitest;
+
+	describe.todo('To Do');
+}
+/* c8 ignore stop */
diff --git a/src/pages/options/Page.svelte b/src/pages/options/Page.svelte
index e57ddac..220920d 100644
--- a/src/pages/options/Page.svelte
+++ b/src/pages/options/Page.svelte
@@ -9,40 +9,49 @@
 	import About from '~/components/About.svelte';
 	import Bookmarks from '~/components/Bookmarks.svelte';
 	import Config from '~/components/Config.svelte';
+	import Message from '~/components/Message.svelte';
 	import TryIt from '~/components/TryIt.svelte';
+	import { messageBox } from '~/lib/messages';
 </script>
 
 <main class="mx-1 mt-4 self-center">
 	<Tabs style="underline">
 		<TabItem open>
 			<div slot="title" class="flex items-center gap-2">
-				<BookmarkOutline size="sm" />
+				<BookmarkOutline size="sm" class="focus:outline-none" />
 				Bookmarks
 			</div>
 			<Bookmarks />
 		</TabItem>
 		<TabItem>
 			<div slot="title" class="flex items-center gap-2">
-				<SearchOutline size="sm" />
+				<SearchOutline size="sm" class="focus:outline-none" />
 				Try It
 			</div>
 			<TryIt />
 		</TabItem>
 		<TabItem>
 			<div slot="title" class="flex items-center gap-2">
-				<UserSettingsOutline size="sm" />
+				<UserSettingsOutline size="sm" class="focus:outline-none" />
 				Settings
 			</div>
 			<Config />
 		</TabItem>
 		<TabItem>
 			<div slot="title" class="flex items-center gap-2">
-				<QuestionCircleOutline size="sm" />
+				<QuestionCircleOutline size="sm" class="focus:outline-none" />
 				About
 			</div>
 			<About />
 		</TabItem>
 	</Tabs>
+
+	<!-- Global message box -->
+	<div class="absolute right-6 top-6 space-y-2">
+		{#each Object.entries($messageBox) as [id, message] (id)}
+			<Message {message} />
+		{/each}
+	</div>
 </main>
 
 <style lang="postcss">