diff --git a/CHANGELOG.md b/CHANGELOG.md
index bdb87e3..08baf69 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+## [1.26.1](https://github.com/rodrigogs/whats-reader/compare/v1.26.0...v1.26.1) (2026-01-05)
+
+
+### Bug Fixes
+
+* header no longer shrinks when side panels expand ([1fa3fc9](https://github.com/rodrigogs/whats-reader/commit/1fa3fc93fbc3e5c3f65d79b55a8799deb6290af7))
+
 # [1.26.0](https://github.com/rodrigogs/whats-reader/compare/v1.25.1...v1.26.0) (2026-01-05)
 
 
diff --git a/package-lock.json b/package-lock.json
index 1c59e7c..a0f6b91 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
 	"name": "whats-reader",
-	"version": "1.26.0",
+	"version": "1.26.1",
 	"lockfileVersion": 3,
 	"requires": true,
 	"packages": {
 		"": {
 			"name": "whats-reader",
-			"version": "1.26.0",
+			"version": "1.26.1",
 			"license": "AGPL-3.0",
 			"dependencies": {
 				"@floating-ui/dom": "^1.7.4",
diff --git a/package.json b/package.json
index 7435e8e..71dd852 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
 	"name": "whats-reader",
 	"productName": "WhatsApp Backup Reader",
-	"version": "1.26.0",
+	"version": "1.26.1",
 	"description": "A desktop app to read and visualize WhatsApp chat exports",
 	"license": "AGPL-3.0",
 	"author": {
diff --git a/src/routes/+page.svelte b/src/routes/+page.svelte
index 24ee59b..d2f9867 100644
--- a/src/routes/+page.svelte
+++ b/src/routes/+page.svelte
@@ -534,61 +534,8 @@ const currentUser = $derived.by(() => {
 	</div>
 	{:else}
 		<!-- Main app layout -->
-		<div class="flex-1 flex overflow-hidden">
-			<!-- Sidebar -->
-			<div
-				class="sidebar-panel w-80 flex-shrink-0 border-r border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-900 flex flex-col {showSidebar ? 'sidebar-open' : 'sidebar-closed'}"
-				class:electron-mac={isElectronMac}
-			>
-				<!-- Sidebar header - empty green bar to match main header -->
-				<div class="h-16 bg-[var(--color-whatsapp-dark-green)] flex-shrink-0"></div>
-				
-				<!-- Chats title bar - matches search bar styling exactly -->
-				<div class="p-3 bg-gray-50 dark:bg-gray-800 border-b border-gray-200 dark:border-gray-700">
-					<label class="relative flex items-center w-full h-10 pl-10 pr-4 bg-gray-100 dark:bg-gray-800 rounded-lg cursor-pointer hover:bg-gray-200 dark:hover:bg-gray-700 transition-colors">
-						<div class="absolute inset-y-0 left-3 flex items-center pointer-events-none">
-							<Icon name="plus" size="md" class="text-gray-400" />
-						</div>
-						<span class="text-gray-500">{m.import_chat()}</span>
-						<input
-							type="file"
-							accept=".txt,.zip"
-							class="hidden"
-							onchange={(e) => {
-								const input = e.target as HTMLInputElement;
-								if (input.files) handleFilesSelected(input.files);
-							}}
-							multiple
-						/>
-					</label>
-				</div>
-
-				<!-- Chat list -->
-				<div class="flex-1 overflow-hidden">
-					<ChatList
-						chats={appState.chats}
-						selectedIndex={appState.selectedChatIndex}
-						onSelect={handleSelectChat}
-						onRemove={handleRemoveChat}
-						{languageByChat}
-						onLanguageChange={handleLanguageChange}
-						{autoLoadMediaByChat}
-						onAutoLoadMediaChange={handleAutoLoadMediaChange}
-						{loadingChats}
-					/>
-				</div>
-			</div>
-
-			<!-- Overlay for mobile sidebar -->
-			{#if showSidebar}
-				<button
-					class="md:hidden fixed inset-0 bg-black/50 z-30"
-					onclick={() => (showSidebar = false)}
-					aria-label={m.sidebar_close()}
-				></button>
-			{/if}
-
-			<!-- Main content -->
+		<div class="flex-1 flex flex-col overflow-hidden">
+			<!-- Top header bar - always full width -->
 			{#if appState.selectedChat}
 				{#snippet perspectiveSelectorContent()}
 					<DropdownHeader title={m.perspective_view_as()} />
@@ -626,175 +573,171 @@ const currentUser = $derived.by(() => {
 					</DropdownList>
 				{/snippet}
 				
-				<div class="flex-1 flex flex-col overflow-hidden">
-					<!-- Chat header -->
-					<div class="h-16 px-4 flex items-center gap-3 bg-[var(--color-whatsapp-dark-green)] text-white shadow-md flex-shrink-0">
-						<!-- Sidebar toggle button -->
-						<IconButton
-							theme="dark"
-							size="md"
-							class="-ml-2"
-							onclick={toggleSidebar}
-							aria-label={m.sidebar_toggle()}
-							title={m.sidebar_toggle()}
+				<!-- Chat header -->
+				<div class="h-16 px-4 flex items-center gap-3 bg-[var(--color-whatsapp-dark-green)] text-white shadow-md flex-shrink-0">
+					<!-- Sidebar toggle button -->
+					<IconButton
+						theme="dark"
+						size="md"
+						class="-ml-2"
+						onclick={toggleSidebar}
+						aria-label={m.sidebar_toggle()}
+						title={m.sidebar_toggle()}
+					>
+						{#if showSidebar}
+							<Icon name="chevron-left" size="md" />
+						{:else}
+							<Icon name="menu" size="md" />
+						{/if}
+					</IconButton>
+					<!-- Avatar -->
+					<div class="w-10 h-10 rounded-full bg-white/20 flex items-center justify-center font-semibold">
+						{appState.selectedChat.title.charAt(0).toUpperCase()}
+					</div>
+
+					<!-- Chat info -->
+					<div class="flex-1 min-w-0">
+						<h2 class="font-semibold truncate">{appState.selectedChat.title}</h2>
+						<button
+							type="button"
+							class="text-xs text-white/70 hover:text-white truncate block max-w-full text-left cursor-pointer transition-colors"
+							onclick={openParticipantsModal}
+						title={m.participants_view_all()}
 						>
-							{#if showSidebar}
-								<Icon name="chevron-left" size="md" />
-							{:else}
-								<Icon name="menu" size="md" />
+							{appState.selectedChat.participants.slice(0, 5).join(', ')}
+							{#if appState.selectedChat.participants.length > 5}
+								{m.perspective_more_participants({ count: appState.selectedChat.participants.length - 5 })}
 							{/if}
-						</IconButton>
-						<!-- Avatar -->
-						<div class="w-10 h-10 rounded-full bg-white/20 flex items-center justify-center font-semibold">
-							{appState.selectedChat.title.charAt(0).toUpperCase()}
-						</div>
+						</button>
+					</div>
 
-						<!-- Chat info -->
-						<div class="flex-1 min-w-0">
-							<h2 class="font-semibold truncate">{appState.selectedChat.title}</h2>
-							<button
-								type="button"
-								class="text-xs text-white/70 hover:text-white truncate block max-w-full text-left cursor-pointer transition-colors"
-								onclick={openParticipantsModal}
-							title={m.participants_view_all()}
+					<!-- Actions -->
+					<div class="flex items-center gap-2">
+						<!-- Small screens: Options menu -->
+						<div class="md:hidden relative">
+							<IconButton
+								bind:ref={chatOptionsButtonRef}
+								theme="dark"
+								size="md"
+								onclick={() => showChatOptionsDropdown = !showChatOptionsDropdown}
+								title={m.chat_options()}
+								aria-label={m.chat_options()}
+							>
+								<Icon name="dots-vertical" size="md" />
+							</IconButton>
+							
+							<Dropdown
+								anchor={chatOptionsButtonRef}
+								open={showChatOptionsDropdown}
+								onClose={() => {
+									showChatOptionsDropdown = false;
+									showPerspectiveDropdown = false;
+									perspectiveSearchQuery = '';
+								}}
+								width="w-56"
+								placement="bottom-end"
 							>
-								{appState.selectedChat.participants.slice(0, 5).join(', ')}
-								{#if appState.selectedChat.participants.length > 5}
-									{m.perspective_more_participants({ count: appState.selectedChat.participants.length - 5 })}
+								{#if showPerspectiveDropdown}
+									<!-- Perspective selector view -->
+									{@render perspectiveSelectorContent()}
+								{:else}
+									<!-- Main options menu -->
+									<DropdownList>
+										<ListItemButton
+											active={!!currentPerspective}
+											onclick={() => showPerspectiveDropdown = true}
+										>
+											<Icon name="user" size="sm" />
+											<span>{m.perspective_view_as()}</span>
+										</ListItemButton>
+										<ListItemButton
+											active={showMediaGallery}
+											onclick={() => {
+												showChatOptionsDropdown = false;
+												toggleMediaGallery();
+											}}
+										>
+											<Icon name="image" size="sm" />
+											<span>{m.media_gallery_title()}</span>
+										</ListItemButton>
+										<ListItemButton
+											active={showBookmarks}
+											onclick={() => {
+												showChatOptionsDropdown = false;
+												toggleBookmarks();
+											}}
+										>
+											<Icon name="bookmark" size="sm" />
+											<span>{m.bookmarks_title()}</span>
+										</ListItemButton>
+										<ListItemButton
+											onclick={() => {
+												showChatOptionsDropdown = false;
+												toggleStats();
+											}}
+										>
+											<Icon name="chart-bar" size="sm" />
+											<span>{m.stats_view()}</span>
+										</ListItemButton>
+									</DropdownList>
 								{/if}
-							</button>
+							</Dropdown>
 						</div>
 
-						<!-- Actions -->
-						<div class="flex items-center gap-2">
-							<!-- Small screens: Options menu -->
-							<div class="md:hidden relative">
+						<!-- Large screens: Individual buttons -->
+						<div class="hidden md:flex items-center gap-2">
+							<!-- Perspective selector -->
+							<div class="relative">
 								<IconButton
-									bind:ref={chatOptionsButtonRef}
+									bind:ref={perspectiveButtonRef}
 									theme="dark"
 									size="md"
-									onclick={() => showChatOptionsDropdown = !showChatOptionsDropdown}
-									title={m.chat_options()}
-									aria-label={m.chat_options()}
+									active={!!currentPerspective}
+									onclick={() => showPerspectiveDropdown = !showPerspectiveDropdown}
+									title={m.perspective_view_as()}
+									aria-label={m.perspective_select()}
 								>
-									<Icon name="dots-vertical" size="md" />
+									<Icon name="user" size="md" />
 								</IconButton>
 								
 								<Dropdown
-									anchor={chatOptionsButtonRef}
-									open={showChatOptionsDropdown}
-									onClose={() => {
-										showChatOptionsDropdown = false;
-										showPerspectiveDropdown = false;
-										perspectiveSearchQuery = '';
-									}}
-									width="w-56"
-									placement="bottom-end"
+									anchor={perspectiveButtonRef}
+									open={showPerspectiveDropdown}
+									onClose={() => { showPerspectiveDropdown = false; perspectiveSearchQuery = ''; }}
 								>
-									{#if showPerspectiveDropdown}
-										<!-- Perspective selector view -->
-										{@render perspectiveSelectorContent()}
-									{:else}
-										<!-- Main options menu -->
-										<DropdownList>
-											<ListItemButton
-												active={!!currentPerspective}
-												onclick={() => showPerspectiveDropdown = true}
-											>
-												<Icon name="user" size="sm" />
-												<span>{m.perspective_view_as()}</span>
-											</ListItemButton>
-											<ListItemButton
-												active={showMediaGallery}
-												onclick={() => {
-													showChatOptionsDropdown = false;
-													toggleMediaGallery();
-												}}
-											>
-												<Icon name="image" size="sm" />
-												<span>{m.media_gallery_title()}</span>
-											</ListItemButton>
-											<ListItemButton
-												active={showBookmarks}
-												onclick={() => {
-													showChatOptionsDropdown = false;
-													toggleBookmarks();
-												}}
-											>
-												<Icon name="bookmark" size="sm" />
-												<span>{m.bookmarks_title()}</span>
-											</ListItemButton>
-											<ListItemButton
-												onclick={() => {
-													showChatOptionsDropdown = false;
-													toggleStats();
-												}}
-											>
-												<Icon name="chart-bar" size="sm" />
-												<span>{m.stats_view()}</span>
-											</ListItemButton>
-										</DropdownList>
-									{/if}
+									{@render perspectiveSelectorContent()}
 								</Dropdown>
 							</div>
 
-							<!-- Large screens: Individual buttons -->
-							<div class="hidden md:flex items-center gap-2">
-								<!-- Perspective selector -->
-								<div class="relative">
-									<IconButton
-										bind:ref={perspectiveButtonRef}
-										theme="dark"
-										size="md"
-										active={!!currentPerspective}
-										onclick={() => showPerspectiveDropdown = !showPerspectiveDropdown}
-										title={m.perspective_view_as()}
-										aria-label={m.perspective_select()}
-									>
-										<Icon name="user" size="md" />
-									</IconButton>
-									
-									<Dropdown
-										anchor={perspectiveButtonRef}
-										open={showPerspectiveDropdown}
-										onClose={() => { showPerspectiveDropdown = false; perspectiveSearchQuery = ''; }}
-									>
-										{@render perspectiveSelectorContent()}
-									</Dropdown>
-								</div>
-
-								<IconButton
-									theme="dark"
-									size="md"
-									active={showMediaGallery}
-									onclick={toggleMediaGallery}
-									title={m.media_gallery_title()}
-									aria-label={m.media_gallery_toggle()}
-								>
-									<Icon name="image" size="md" filled={showMediaGallery} />
-								</IconButton>
-								<IconButton
-									theme="dark"
-									size="md"
-									active={showBookmarks}
-									onclick={toggleBookmarks}
-									title={m.bookmarks_title()}
-									aria-label={m.bookmarks_toggle()}
-								>
-									<Icon name="bookmark" size="md" filled={showBookmarks} />
-								</IconButton>
-								<IconButton
-									theme="dark"
-									size="md"
-									onclick={toggleStats}
-									title={m.stats_view()}
-									aria-label={m.stats_view()}
-								>
-									<Icon name="chart-bar" size="md" />
-								</IconButton>
-							</div>
-
-							<!-- Always visible: Locale and Theme -->
+							<IconButton
+								theme="dark"
+								size="md"
+								active={showMediaGallery}
+								onclick={toggleMediaGallery}
+								title={m.media_gallery_title()}
+								aria-label={m.media_gallery_toggle()}
+							>
+								<Icon name="image" size="md" filled={showMediaGallery} />
+							</IconButton>
+							<IconButton
+								theme="dark"
+								size="md"
+								active={showBookmarks}
+								onclick={toggleBookmarks}
+								title={m.bookmarks_title()}
+								aria-label={m.bookmarks_toggle()}
+							>
+								<Icon name="bookmark" size="md" filled={showBookmarks} />
+							</IconButton>
+							<IconButton
+								theme="dark"
+								size="md"
+								onclick={toggleStats}
+								title={m.stats_view()}
+								aria-label={m.stats_view()}
+							>
+								<Icon name="chart-bar" size="md" />
+							</IconButton>
 							<LocaleSwitcher variant="header" />
 							<IconButton
 								theme="dark"
@@ -811,7 +754,84 @@ const currentUser = $derived.by(() => {
 							</IconButton>
 						</div>
 					</div>
+				</div>
+			{:else}
+				<!-- No chat selected - simplified header -->
+				<div class="h-16 px-4 flex items-center bg-[var(--color-whatsapp-dark-green)] flex-shrink-0">
+					<!-- Sidebar toggle button -->
+					<IconButton
+						theme="dark"
+						size="md"
+						class="-ml-2"
+						onclick={toggleSidebar}
+						aria-label={m.sidebar_toggle()}
+						title={m.sidebar_toggle()}
+					>
+						{#if showSidebar}
+							<Icon name="chevron-left" size="md" />
+						{:else}
+							<Icon name="menu" size="md" />
+						{/if}
+					</IconButton>
+				</div>
+			{/if}
 
+			<!-- Content area below header -->
+			<div class="flex-1 flex overflow-hidden">
+				<!-- Sidebar -->
+				<div
+					class="sidebar-panel w-80 flex-shrink-0 border-r border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-900 flex flex-col {showSidebar ? 'sidebar-open' : 'sidebar-closed'}"
+					class:electron-mac={isElectronMac}
+				>
+				
+				<!-- Chats title bar - matches search bar styling exactly -->
+				<div class="p-3 bg-gray-50 dark:bg-gray-800 border-b border-gray-200 dark:border-gray-700">
+					<label class="relative flex items-center w-full h-10 pl-10 pr-4 bg-gray-100 dark:bg-gray-800 rounded-lg cursor-pointer hover:bg-gray-200 dark:hover:bg-gray-700 transition-colors">
+						<div class="absolute inset-y-0 left-3 flex items-center pointer-events-none">
+							<Icon name="plus" size="md" class="text-gray-400" />
+						</div>
+						<span class="text-gray-500">{m.import_chat()}</span>
+						<input
+							type="file"
+							accept=".txt,.zip"
+							class="hidden"
+							onchange={(e) => {
+								const input = e.target as HTMLInputElement;
+								if (input.files) handleFilesSelected(input.files);
+							}}
+							multiple
+						/>
+					</label>
+				</div>
+
+				<!-- Chat list -->
+				<div class="flex-1 overflow-hidden">
+					<ChatList
+						chats={appState.chats}
+						selectedIndex={appState.selectedChatIndex}
+						onSelect={handleSelectChat}
+						onRemove={handleRemoveChat}
+						{languageByChat}
+						onLanguageChange={handleLanguageChange}
+						{autoLoadMediaByChat}
+						onAutoLoadMediaChange={handleAutoLoadMediaChange}
+						{loadingChats}
+					/>
+				</div>
+			</div>
+
+			<!-- Overlay for mobile sidebar -->
+			{#if showSidebar}
+				<button
+					class="md:hidden fixed inset-0 bg-black/50 z-30"
+					onclick={() => (showSidebar = false)}
+					aria-label={m.sidebar_close()}
+				></button>
+			{/if}
+
+			<!-- Main content -->
+			{#if appState.selectedChat}
+				<div class="flex-1 flex flex-col overflow-hidden">
 					<!-- Search bar -->
 					<div class="p-3 bg-gray-50 dark:bg-gray-800 border-b border-gray-200 dark:border-gray-700">
 						<div class="flex items-center gap-2">
@@ -895,8 +915,6 @@ const currentUser = $derived.by(() => {
 					class="gallery-panel w-96 flex-shrink-0 border-l border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-900 flex flex-col {showMediaGallery ? 'gallery-open' : 'gallery-closed'}"
 					class:electron-mac={isElectronMac}
 				>
-					<!-- Header spacer - matches sidebar header -->
-					<div class="h-16 bg-[var(--color-whatsapp-dark-green)] flex-shrink-0"></div>
 					<div class="flex-1 overflow-hidden">
 						<MediaGallery
 							onNavigateToMessage={handleNavigateToMediaMessage}
@@ -910,9 +928,6 @@ const currentUser = $derived.by(() => {
 					class="bookmarks-panel w-80 flex-shrink-0 border-l border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-900 flex flex-col {showBookmarks ? 'bookmarks-open' : 'bookmarks-closed'}"
 					class:electron-mac={isElectronMac}
 				>
-					<!-- Bookmarks header - matches sidebar header -->
-					<div class="h-16 bg-[var(--color-whatsapp-dark-green)] flex-shrink-0"></div>
-					
 					<!-- Bookmarks content -->
 					<div class="flex-1 overflow-hidden">
 						<BookmarksPanel
@@ -992,34 +1007,16 @@ const currentUser = $derived.by(() => {
 				</Modal>
 			{:else}
 				<!-- No chat selected -->
-				<div class="flex-1 flex flex-col bg-gray-50 dark:bg-gray-900">
-					<div class="h-16 px-4 flex items-center bg-[var(--color-whatsapp-dark-green)] flex-shrink-0">
-						<!-- Sidebar toggle button -->
-						<IconButton
-							theme="dark"
-							size="md"
-							class="-ml-2"
-							onclick={toggleSidebar}
-							aria-label={m.sidebar_toggle()}
-							title={m.sidebar_toggle()}
-						>
-							{#if showSidebar}
-								<Icon name="chevron-left" size="md" />
-							{:else}
-								<Icon name="menu" size="md" />
-							{/if}
-						</IconButton>
-					</div>
-					<div class="flex-1 flex items-center justify-center">
-						<div class="text-center text-gray-500 dark:text-gray-400">
-							<Icon name="chat" size="2xl" class="mx-auto mb-4 opacity-50" />
-							<p>{m.chat_select()}</p>
-						</div>
+				<div class="flex-1 flex items-center justify-center bg-gray-50 dark:bg-gray-900">
+					<div class="text-center text-gray-500 dark:text-gray-400">
+						<Icon name="chat" size="2xl" class="mx-auto mb-4 opacity-50" />
+						<p>{m.chat_select()}</p>
 					</div>
 				</div>
 			{/if}
 		</div>
-	{/if}
+	</div>
+{/if}
 </div>
 
 <!-- Auto-update toast notification (Electron only) -->