diff --git a/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneFragment.kt b/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneFragment.kt
index e938b9c3fe..c281cb6aae 100644
--- a/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneFragment.kt
+++ b/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneFragment.kt
@@ -17,6 +17,7 @@
  */
 package com.infomaniak.mail.ui.main.folder
 
+import android.content.res.Configuration
 import android.os.Bundle
 import android.view.View
 import androidx.fragment.app.Fragment
@@ -30,6 +31,7 @@ import com.infomaniak.mail.MatomoMail.trackNewMessageEvent
 import com.infomaniak.mail.R
 import com.infomaniak.mail.data.cache.mailboxContent.FolderController
 import com.infomaniak.mail.data.models.thread.Thread
+import com.infomaniak.mail.ui.MainActivity
 import com.infomaniak.mail.ui.MainViewModel
 import com.infomaniak.mail.ui.main.NoAnimSlidingPaneLayout
 import com.infomaniak.mail.ui.main.search.SearchFragment
@@ -77,6 +79,11 @@ abstract class TwoPaneFragment : Fragment() {
         observeThreadNavigation()
     }
 
+    override fun onConfigurationChanged(newConfig: Configuration) {
+        super.onConfigurationChanged(newConfig)
+        updateDrawerLockMode()
+    }
+
     private fun setupSlidingPane() = with(slidingPaneLayout) {
         lockMode = SlidingPaneLayout.LOCK_MODE_LOCKED
         addPanelSlideListener(object : SlidingPaneLayout.PanelSlideListener {
@@ -121,7 +128,10 @@ abstract class TwoPaneFragment : Fragment() {
             val isOpeningThread = threadUid != null
             if (isOpeningThread) {
                 val hasOpened = slidingPaneLayout.openPaneNoAnimation()
-                if (hasOpened) setSystemBarsColors(statusBarColor = R.color.backgroundColor, navigationBarColor = null)
+                if (hasOpened) {
+                    updateDrawerLockMode()
+                    setSystemBarsColors(statusBarColor = R.color.backgroundColor, navigationBarColor = null)
+                }
             } else {
                 resetPanes()
             }
@@ -160,6 +170,7 @@ abstract class TwoPaneFragment : Fragment() {
     private fun resetPanes() {
 
         val hasClosed = slidingPaneLayout.closePaneNoAnimation()
+        updateDrawerLockMode()
 
         if (hasClosed) {
             setSystemBarsColors(
@@ -172,4 +183,13 @@ abstract class TwoPaneFragment : Fragment() {
 
         childFragmentManager.beginTransaction().replace(R.id.threadHostFragment, ThreadFragment()).commit()
     }
+
+    // TODO: When we'll add the feature of swiping between Threads, we'll need to check if this function is still needed.
+    private fun updateDrawerLockMode() {
+        if (this is ThreadListFragment) {
+            (requireActivity() as MainActivity).setDrawerLockMode(
+                isLocked = twoPaneViewModel.isInThreadInPhoneMode(requireContext()),
+            )
+        }
+    }
 }
diff --git a/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneViewModel.kt b/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneViewModel.kt
index 6ed72a541c..c72f72c8c0 100644
--- a/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneViewModel.kt
+++ b/app/src/main/java/com/infomaniak/mail/ui/main/folder/TwoPaneViewModel.kt
@@ -32,7 +32,7 @@ import com.infomaniak.mail.data.models.message.Message
 import com.infomaniak.mail.data.models.thread.Thread
 import com.infomaniak.mail.ui.newMessage.NewMessageActivityArgs
 import com.infomaniak.mail.utils.Utils.runCatchingRealm
-import com.infomaniak.mail.utils.canDisplayBothPanes
+import com.infomaniak.mail.utils.canDisplayOnlyOnePane
 import dagger.hilt.android.lifecycle.HiltViewModel
 import javax.inject.Inject
 
@@ -94,7 +94,7 @@ class TwoPaneViewModel @Inject constructor(
         )
     }
 
-    fun isInThreadInPhoneMode(context: Context): Boolean = isThreadOpen && !context.canDisplayBothPanes()
+    fun isInThreadInPhoneMode(context: Context): Boolean = isThreadOpen && context.canDisplayOnlyOnePane()
 
     data class NavData(
         @IdRes val resId: Int,
diff --git a/app/src/main/java/com/infomaniak/mail/utils/Extensions.kt b/app/src/main/java/com/infomaniak/mail/utils/Extensions.kt
index a4701d0d20..ddd2f34da2 100644
--- a/app/src/main/java/com/infomaniak/mail/utils/Extensions.kt
+++ b/app/src/main/java/com/infomaniak/mail/utils/Extensions.kt
@@ -159,8 +159,10 @@ fun Date.isLastWeek(): Boolean {
 //region UI
 fun Context.isInPortrait(): Boolean = resources.configuration.orientation == Configuration.ORIENTATION_PORTRAIT
 
-fun Fragment.canDisplayBothPanes(): Boolean = requireContext().canDisplayBothPanes()
 fun Context.canDisplayBothPanes(): Boolean = resources.getBoolean(R.bool.canDisplayBothPanes)
+fun Fragment.canDisplayBothPanes(): Boolean = requireContext().canDisplayBothPanes()
+fun Context.canDisplayOnlyOnePane(): Boolean = !canDisplayBothPanes()
+fun Fragment.canDisplayOnlyOnePane(): Boolean = requireContext().canDisplayOnlyOnePane()
 
 fun View.toggleChevron(
     isCollapsed: Boolean,