diff --git a/app/src/main/java/org/kiwix/kiwixmobile/nav/destination/reader/KiwixReaderFragment.kt b/app/src/main/java/org/kiwix/kiwixmobile/nav/destination/reader/KiwixReaderFragment.kt
index 0318c7a393..82da05e718 100644
--- a/app/src/main/java/org/kiwix/kiwixmobile/nav/destination/reader/KiwixReaderFragment.kt
+++ b/app/src/main/java/org/kiwix/kiwixmobile/nav/destination/reader/KiwixReaderFragment.kt
@@ -33,7 +33,11 @@ import android.view.ViewGroup
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.net.toFile
 import androidx.drawerlayout.widget.DrawerLayout
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.lifecycleScope
+import androidx.lifecycle.repeatOnLifecycle
 import com.google.android.material.bottomnavigation.BottomNavigationView
+import kotlinx.coroutines.launch
 import org.kiwix.kiwixmobile.R
 import org.kiwix.kiwixmobile.cachedComponent
 import org.kiwix.kiwixmobile.core.R.anim
@@ -71,44 +75,52 @@ class KiwixReaderFragment : CoreReaderFragment() {
 
   override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
     super.onViewCreated(view, savedInstanceState)
-
-    val activity = activity as CoreMainActivity
-    noOpenBookButton?.setOnClickListener {
-      activity.navigate(
-        KiwixReaderFragmentDirections.actionNavigationReaderToNavigationLibrary()
-      )
+    lifecycleScope.launch {
+      viewLifecycleOwner.repeatOnLifecycle(Lifecycle.State.STARTED) {
+        val activity = activity as CoreMainActivity
+        noOpenBookButton?.setOnClickListener {
+          activity.navigate(
+            KiwixReaderFragmentDirections.actionNavigationReaderToNavigationLibrary()
+          )
+        }
+        activity.supportActionBar?.setDisplayHomeAsUpEnabled(true)
+        toolbar?.let(activity::setupDrawerToggle)
+        setFragmentContainerBottomMarginToSizeOfNavBar()
+        openPageInBookFromNavigationArguments()
+      }
     }
-    activity.supportActionBar?.setDisplayHomeAsUpEnabled(true)
-    toolbar?.let(activity::setupDrawerToggle)
-    setFragmentContainerBottomMarginToSizeOfNavBar()
-    openPageInBookFromNavigationArguments()
   }
 
-  private fun openPageInBookFromNavigationArguments() {
+  @Suppress("TooGenericExceptionCaught")
+  private suspend fun openPageInBookFromNavigationArguments() {
     val args = KiwixReaderFragmentArgs.fromBundle(requireArguments())
-
-    if (args.pageUrl.isNotEmpty()) {
-      if (args.zimFileUri.isNotEmpty()) {
-        tryOpeningZimFile(args.zimFileUri)
-      } else {
-        // Set up bookmarks for the current book when opening bookmarks from the Bookmark screen.
-        // This is necessary because we are not opening the ZIM file again; the bookmark is
-        // inside the currently opened book. Bookmarks are set up when opening the ZIM file.
-        // See https://github.com/kiwix/kiwix-android/issues/3541
-        zimReaderContainer?.zimFileReader?.let(::setUpBookmarks)
-      }
-      loadUrlWithCurrentWebview(args.pageUrl)
-    } else {
-      if (args.zimFileUri.isNotEmpty()) {
-        tryOpeningZimFile(args.zimFileUri)
+    try {
+      if (args.pageUrl.isNotEmpty()) {
+        if (args.zimFileUri.isNotEmpty()) {
+          tryOpeningZimFile(args.zimFileUri)
+        } else {
+          // Set up bookmarks for the current book when opening bookmarks from the Bookmark screen.
+          // This is necessary because we are not opening the ZIM file again; the bookmark is
+          // inside the currently opened book. Bookmarks are set up when opening the ZIM file.
+          // See https://github.com/kiwix/kiwix-android/issues/3541
+          zimReaderContainer?.zimFileReader?.let(::setUpBookmarks)
+        }
+        loadUrlWithCurrentWebview(args.pageUrl)
       } else {
-        manageExternalLaunchAndRestoringViewState()
+        if (args.zimFileUri.isNotEmpty()) {
+          tryOpeningZimFile(args.zimFileUri)
+        } else {
+          manageExternalLaunchAndRestoringViewState()
+        }
       }
+    } catch (error: Exception) {
+      Log.e("KiwixReader", "Error opening ZIM file", error)
+    } finally {
+      requireArguments().clear()
     }
-    requireArguments().clear()
   }
 
-  private fun tryOpeningZimFile(zimFileUri: String) {
+  private suspend fun tryOpeningZimFile(zimFileUri: String) {
     val filePath = FileUtils.getLocalFilePathByUri(
       requireActivity().applicationContext, Uri.parse(zimFileUri)
     )
@@ -155,14 +167,16 @@ class KiwixReaderFragment : CoreReaderFragment() {
         contentFrame?.visibility = View.VISIBLE
       }
       mainMenu?.showWebViewOptions(true)
-      if (webViewList.isEmpty()) {
-        exitBook()
-      } else {
-        // Reset the top margin of web views to 0 to remove any previously set margin
-        // This ensures that the web views are displayed without any additional
-        // top margin for kiwix main app.
-        setTopMarginToWebViews(0)
-        selectTab(currentWebViewIndex)
+      lifecycleScope.launch {
+        if (webViewList.isEmpty()) {
+          exitBook()
+        } else {
+          // Reset the top margin of web views to 0 to remove any previously set margin
+          // This ensures that the web views are displayed without any additional
+          // top margin for kiwix main app.
+          setTopMarginToWebViews(0)
+          selectTab(currentWebViewIndex)
+        }
       }
     }
   }
@@ -199,17 +213,19 @@ class KiwixReaderFragment : CoreReaderFragment() {
 
   override fun onResume() {
     super.onResume()
-    if (zimReaderContainer?.zimFile == null &&
-      zimReaderContainer?.zimFileReader?.assetFileDescriptorList?.isEmpty() == true
-    ) {
-      exitBook()
-    }
-    if (isFullScreenVideo || isInFullScreenMode()) {
-      hideNavBar()
+    lifecycleScope.launch {
+      if (zimReaderContainer?.zimFile == null &&
+        zimReaderContainer?.zimFileReader?.assetFileDescriptorList?.isEmpty() == true
+      ) {
+        exitBook()
+      }
+      if (isFullScreenVideo || isInFullScreenMode()) {
+        hideNavBar()
+      }
     }
   }
 
-  override fun restoreViewStateOnInvalidJSON() {
+  override suspend fun restoreViewStateOnInvalidJSON() {
     Log.d(TAG_KIWIX, "Kiwix normal start, no zimFile loaded last time  -> display home page")
     exitBook()
   }
@@ -222,20 +238,22 @@ class KiwixReaderFragment : CoreReaderFragment() {
     val settings = requireActivity().getSharedPreferences(SharedPreferenceUtil.PREF_KIWIX_MOBILE, 0)
     val zimFile = settings.getString(TAG_CURRENT_FILE, null)
 
-    if (zimFile != null && File(zimFile).isFileExist()) {
-      if (zimReaderContainer?.zimFile == null) {
-        openZimFile(File(zimFile))
-        Log.d(
-          TAG_KIWIX,
-          "Kiwix normal start, Opened last used zimFile: -> $zimFile"
-        )
+    lifecycleScope.launch {
+      if (zimFile != null && File(zimFile).isFileExist()) {
+        if (zimReaderContainer?.zimFile == null) {
+          openZimFile(File(zimFile))
+          Log.d(
+            TAG_KIWIX,
+            "Kiwix normal start, Opened last used zimFile: -> $zimFile"
+          )
+        } else {
+          zimReaderContainer?.zimFileReader?.let(::setUpBookmarks)
+        }
       } else {
-        zimReaderContainer?.zimFileReader?.let(::setUpBookmarks)
+        getCurrentWebView()?.snack(R.string.zim_not_opened)
+        exitBook() // hide the options for zim file to avoid unexpected UI behavior
+        return@launch // book not found so don't need to restore the tabs for this file
       }
-    } else {
-      getCurrentWebView()?.snack(R.string.zim_not_opened)
-      exitBook() // hide the options for zim file to avoid unexpected UI behavior
-      return // book not found so don't need to restore the tabs for this file
     }
     restoreTabs(zimArticles, zimPositions, currentTab)
   }
@@ -304,10 +322,12 @@ class KiwixReaderFragment : CoreReaderFragment() {
       when (it.scheme) {
         "file" -> {
           Handler(Looper.getMainLooper()).postDelayed({
-            openZimFile(it.toFile()).also {
-              // if used once then clear it to avoid affecting any other functionality
-              // of the application.
-              requireActivity().intent.action = null
+            lifecycleScope.launch {
+              openZimFile(it.toFile()).also {
+                // if used once then clear it to avoid affecting any other functionality
+                // of the application.
+                requireActivity().intent.action = null
+              }
             }
           }, 300)
         }
@@ -315,7 +335,9 @@ class KiwixReaderFragment : CoreReaderFragment() {
         "content" -> {
           Handler(Looper.getMainLooper()).postDelayed({
             getZimFileFromUri(it)?.let { zimFile ->
-              openZimFile(zimFile)
+              lifecycleScope.launch {
+                openZimFile(zimFile)
+              }
             }.also {
               requireActivity().intent.action = null
             }
diff --git a/app/src/main/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModel.kt b/app/src/main/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModel.kt
index 275a2311a2..a3e9c08137 100644
--- a/app/src/main/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModel.kt
+++ b/app/src/main/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModel.kt
@@ -23,6 +23,7 @@ import android.net.ConnectivityManager
 import androidx.annotation.VisibleForTesting
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
 import io.reactivex.Flowable
 import io.reactivex.disposables.CompositeDisposable
 import io.reactivex.disposables.Disposable
@@ -164,7 +165,7 @@ class ZimManageViewModel @Inject constructor(
       when (it) {
         is RequestNavigateTo -> OpenFileWithNavigation(it.bookOnDisk)
         is RequestMultiSelection -> startMultiSelectionAndSelectBook(it.bookOnDisk)
-        RequestDeleteMultiSelection -> DeleteFiles(selectionsFromState())
+        RequestDeleteMultiSelection -> DeleteFiles(selectionsFromState(), viewModelScope)
         RequestShareMultiSelection -> ShareFiles(selectionsFromState())
         MultiModeFinished -> noSideEffectAndClearSelectionState()
         is RequestSelect -> noSideEffectSelectBook(it.bookOnDisk)
diff --git a/app/src/main/java/org/kiwix/kiwixmobile/zimManager/fileselectView/effects/DeleteFiles.kt b/app/src/main/java/org/kiwix/kiwixmobile/zimManager/fileselectView/effects/DeleteFiles.kt
index 4c75a9c8e3..faf456612a 100644
--- a/app/src/main/java/org/kiwix/kiwixmobile/zimManager/fileselectView/effects/DeleteFiles.kt
+++ b/app/src/main/java/org/kiwix/kiwixmobile/zimManager/fileselectView/effects/DeleteFiles.kt
@@ -19,6 +19,8 @@
 package org.kiwix.kiwixmobile.zimManager.fileselectView.effects
 
 import androidx.appcompat.app.AppCompatActivity
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
 import org.kiwix.kiwixmobile.R
 import org.kiwix.kiwixmobile.cachedComponent
 import org.kiwix.kiwixmobile.core.base.BaseActivity
@@ -33,7 +35,10 @@ import org.kiwix.kiwixmobile.core.utils.files.FileUtils
 import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BooksOnDiskListItem.BookOnDisk
 import javax.inject.Inject
 
-data class DeleteFiles(private val booksOnDiskListItems: List<BookOnDisk>) :
+data class DeleteFiles(
+  private val booksOnDiskListItems: List<BookOnDisk>,
+  private val coroutineScope: CoroutineScope
+) :
   SideEffect<Unit> {
 
   @Inject lateinit var dialogShower: DialogShower
@@ -42,21 +47,22 @@ data class DeleteFiles(private val booksOnDiskListItems: List<BookOnDisk>) :
 
   override fun invokeWith(activity: AppCompatActivity) {
     (activity as BaseActivity).cachedComponent.inject(this)
-
     val name = booksOnDiskListItems.joinToString(separator = "\n") { it.book.title }
 
     dialogShower.show(DeleteZims(name), {
-      activity.toast(
-        if (booksOnDiskListItems.deleteAll()) {
-          R.string.delete_zims_toast
-        } else {
-          R.string.delete_zim_failed
-        }
-      )
+      coroutineScope.launch {
+        activity.toast(
+          if (booksOnDiskListItems.deleteAll()) {
+            R.string.delete_zims_toast
+          } else {
+            R.string.delete_zim_failed
+          }
+        )
+      }
     })
   }
 
-  private fun List<BookOnDisk>.deleteAll(): Boolean {
+  private suspend fun List<BookOnDisk>.deleteAll(): Boolean {
     return fold(true) { acc, book ->
       acc && deleteSpecificZimFile(book).also {
         if (it && book.file.canonicalPath == zimReaderContainer.zimCanonicalPath) {
diff --git a/app/src/test/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModelTest.kt b/app/src/test/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModelTest.kt
index 4810efdc5f..596914b914 100644
--- a/app/src/test/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModelTest.kt
+++ b/app/src/test/java/org/kiwix/kiwixmobile/zimManager/ZimManageViewModelTest.kt
@@ -22,6 +22,7 @@ import android.app.Application
 import android.net.ConnectivityManager
 import android.net.NetworkCapabilities
 import android.net.NetworkCapabilities.TRANSPORT_WIFI
+import androidx.lifecycle.viewModelScope
 import com.jraska.livedata.test
 import io.mockk.clearAllMocks
 import io.mockk.every
@@ -470,7 +471,7 @@ class ZimManageViewModelTest {
         FileSelectListState(listOf(selectedBook, bookOnDisk()), NORMAL)
       viewModel.sideEffects.test()
         .also { viewModel.fileSelectActions.offer(RequestDeleteMultiSelection) }
-        .assertValues(DeleteFiles(listOf(selectedBook)))
+        .assertValues(DeleteFiles(listOf(selectedBook), viewModel.viewModelScope))
     }
 
     @Test
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/main/CoreReaderFragment.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/main/CoreReaderFragment.kt
index 8cbd228a5a..d649c65ac0 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/main/CoreReaderFragment.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/main/CoreReaderFragment.kt
@@ -77,6 +77,7 @@ import androidx.core.widget.ContentLoadingProgressBar
 import androidx.drawerlayout.widget.DrawerLayout
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.Observer
+import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.ItemTouchHelper
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
@@ -95,6 +96,7 @@ import io.reactivex.Flowable
 import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.disposables.Disposable
 import io.reactivex.processors.BehaviorProcessor
+import kotlinx.coroutines.launch
 import org.json.JSONArray
 import org.json.JSONException
 import org.kiwix.kiwixmobile.core.BuildConfig
@@ -1292,7 +1294,7 @@ abstract class CoreReaderFragment :
     mainMenu?.showBookSpecificMenuItems()
   }
 
-  protected fun exitBook() {
+  protected suspend fun exitBook() {
     showNoBookOpenViews()
     bottomToolbar?.visibility = View.GONE
     actionBar?.title = getString(R.string.reader)
@@ -1301,7 +1303,7 @@ abstract class CoreReaderFragment :
     closeZimBook()
   }
 
-  private fun closeZimBook() {
+  private suspend fun closeZimBook() {
     zimReaderContainer?.setZimFile(null)
   }
 
@@ -1320,7 +1322,6 @@ abstract class CoreReaderFragment :
           LinearLayout.LayoutParams.MATCH_PARENT
         )
       }
-      zimReaderContainer?.setZimFile(tempZimFileForUndo)
       webViewList.add(index, it)
       tabsAdapter?.notifyDataSetChanged()
       snackBarRoot?.let { root ->
@@ -1561,7 +1562,7 @@ abstract class CoreReaderFragment :
     unsupportedMimeTypeHandler?.showSaveOrOpenUnsupportedFilesDialog(url, documentType)
   }
 
-  fun openZimFile(
+  suspend fun openZimFile(
     file: File?,
     isCustomApp: Boolean = false,
     assetFileDescriptorList: List<AssetFileDescriptor> = emptyList(),
@@ -1610,11 +1611,12 @@ abstract class CoreReaderFragment :
     )
   }
 
-  private fun openAndSetInContainer(
+  private suspend fun openAndSetInContainer(
     file: File? = null,
     assetFileDescriptorList: List<AssetFileDescriptor> = emptyList(),
     filePath: String? = null
   ) {
+    progressBar?.visibility = View.VISIBLE
     try {
       if (isNotPreviouslyOpenZim(file?.canonicalPath)) {
         webViewList.clear()
@@ -1641,6 +1643,7 @@ abstract class CoreReaderFragment :
       } ?: kotlin.run {
         requireActivity().toast(R.string.error_file_invalid, Toast.LENGTH_LONG)
       }
+      progressBar?.visibility = View.GONE
     }
   }
 
@@ -1675,18 +1678,22 @@ abstract class CoreReaderFragment :
   ) {
     when (requestCode) {
       REQUEST_STORAGE_PERMISSION -> {
-        if (hasPermission(Manifest.permission.READ_EXTERNAL_STORAGE)) {
-          file?.let(::openZimFile)
-        } else {
-          snackBarRoot?.let { snackBarRoot ->
-            Snackbar.make(snackBarRoot, R.string.request_storage, Snackbar.LENGTH_LONG)
-              .setAction(R.string.menu_settings) {
-                val intent = Intent()
-                intent.action = Settings.ACTION_APPLICATION_DETAILS_SETTINGS
-                val uri = Uri.fromParts("package", requireActivity().packageName, null)
-                intent.data = uri
-                startActivity(intent)
-              }.show()
+        lifecycleScope.launch {
+          if (hasPermission(Manifest.permission.READ_EXTERNAL_STORAGE)) {
+            file?.let { file ->
+              openZimFile(file)
+            }
+          } else {
+            snackBarRoot?.let { snackBarRoot ->
+              Snackbar.make(snackBarRoot, R.string.request_storage, Snackbar.LENGTH_LONG)
+                .setAction(R.string.menu_settings) {
+                  val intent = Intent()
+                  intent.action = Settings.ACTION_APPLICATION_DETAILS_SETTINGS
+                  val uri = Uri.fromParts("package", requireActivity().packageName, null)
+                  intent.data = uri
+                  startActivity(intent)
+                }.show()
+            }
           }
         }
       }
@@ -1733,7 +1740,6 @@ abstract class CoreReaderFragment :
 
   private fun restoreDeletedTabs() {
     if (tempWebViewListForUndo.isNotEmpty()) {
-      zimReaderContainer?.setZimFile(tempZimFileForUndo)
       webViewList.addAll(tempWebViewListForUndo)
       tabsAdapter?.notifyDataSetChanged()
       snackBarRoot?.let { root ->
@@ -2281,7 +2287,7 @@ abstract class CoreReaderFragment :
   private fun isInvalidJson(jsonString: String?): Boolean =
     jsonString == null || jsonString == "[]"
 
-  protected fun manageExternalLaunchAndRestoringViewState() {
+  protected suspend fun manageExternalLaunchAndRestoringViewState() {
     val settings = requireActivity().getSharedPreferences(
       SharedPreferenceUtil.PREF_KIWIX_MOBILE,
       0
@@ -2415,5 +2421,5 @@ abstract class CoreReaderFragment :
    * KiwixReaderFragment.restoreViewStateOnInvalidJSON) to ensure consistent behavior
    * when handling invalid JSON scenarios.
    */
-  abstract fun restoreViewStateOnInvalidJSON()
+  abstract suspend fun restoreViewStateOnInvalidJSON()
 }
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/PageFragment.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/PageFragment.kt
index 825f9f56f4..5a9fb51b99 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/PageFragment.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/PageFragment.kt
@@ -195,14 +195,22 @@ abstract class PageFragment : OnItemClickListener, BaseFragment(), FragmentActiv
     pageAdapter.items = state.visiblePageItems
     fragmentPageBinding?.pageSwitch?.isEnabled = !state.isInSelectionState
     fragmentPageBinding?.noPage?.visibility = if (state.pageItems.isEmpty()) VISIBLE else GONE
-    if (state.isInSelectionState) {
-      if (actionMode == null) {
-        actionMode =
-          (requireActivity() as AppCompatActivity).startSupportActionMode(actionModeCallback)
+    when {
+      state.isInSelectionState -> {
+        if (actionMode == null) {
+          actionMode =
+            (requireActivity() as AppCompatActivity).startSupportActionMode(actionModeCallback)
+        }
+        actionMode?.title = getString(R.string.selected_items, state.numberOfSelectedItems())
+      }
+
+      state.isLoading -> {
+        fragmentPageBinding?.loadingZimfileContent?.visibility = View.VISIBLE
+      }
+
+      else -> {
+        actionMode?.finish()
       }
-      actionMode?.title = getString(R.string.selected_items, state.numberOfSelectedItems())
-    } else {
-      actionMode?.finish()
     }
   }
 
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkState.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkState.kt
index aea012598e..09ed196162 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkState.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkState.kt
@@ -26,7 +26,8 @@ data class BookmarkState(
   override val pageItems: List<LibkiwixBookmarkItem>,
   override val showAll: Boolean,
   override val currentZimId: String?,
-  override val searchTerm: String = ""
+  override val searchTerm: String = "",
+  override val isLoading: Boolean
 ) : PageState<LibkiwixBookmarkItem>() {
   override val visiblePageItems: List<PageRelated> = filteredPageItems
 
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkViewModel.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkViewModel.kt
index f491ddc782..cee6592faa 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkViewModel.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/viewmodel/BookmarkViewModel.kt
@@ -40,7 +40,15 @@ class BookmarkViewModel @Inject constructor(
 ) {
 
   override fun initialState(): BookmarkState =
-    BookmarkState(emptyList(), sharedPreferenceUtil.showBookmarksAllBooks, zimReaderContainer.id)
+    BookmarkState(
+      emptyList(),
+      sharedPreferenceUtil.showBookmarksAllBooks,
+      zimReaderContainer.id,
+      isLoading = false
+    )
+
+  override fun loadData(state: BookmarkState, action: Action.LoadingData): BookmarkState =
+    state.copy(isLoading = action.isLoading)
 
   override fun updatePagesBasedOnFilter(
     state: BookmarkState,
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryState.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryState.kt
index 10ea0b37a8..fa925723b2 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryState.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryState.kt
@@ -28,7 +28,8 @@ data class HistoryState(
   override val pageItems: List<HistoryItem>,
   override val showAll: Boolean,
   override val currentZimId: String?,
-  override val searchTerm: String = ""
+  override val searchTerm: String = "",
+  override val isLoading: Boolean
 ) : PageState<HistoryItem>() {
   override val visiblePageItems: List<HistoryListItem> =
     HeaderizableList<HistoryListItem, HistoryItem, DateItem>(filteredPageItems)
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryViewModel.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryViewModel.kt
index 5a9493cdd4..04892bb173 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryViewModel.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/history/viewmodel/HistoryViewModel.kt
@@ -36,7 +36,15 @@ class HistoryViewModel @Inject constructor(
 ) : PageViewModel<HistoryItem, HistoryState>(historyRoomDao, sharedPrefs, zimReaderContainer) {
 
   override fun initialState(): HistoryState =
-    HistoryState(emptyList(), sharedPreferenceUtil.showHistoryAllBooks, zimReaderContainer.id)
+    HistoryState(
+      emptyList(),
+      sharedPreferenceUtil.showHistoryAllBooks,
+      zimReaderContainer.id,
+      isLoading = false
+    )
+
+  override fun loadData(state: HistoryState, action: Action.LoadingData): HistoryState =
+    state.copy(isLoading = action.isLoading)
 
   override fun updatePagesBasedOnFilter(
     state: HistoryState,
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesState.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesState.kt
index 948926b77e..286e35ca40 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesState.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesState.kt
@@ -26,7 +26,8 @@ data class NotesState(
   override val pageItems: List<NoteListItem>,
   override val showAll: Boolean,
   override val currentZimId: String?,
-  override val searchTerm: String = ""
+  override val searchTerm: String = "",
+  override val isLoading: Boolean,
 ) : PageState<NoteListItem>() {
   override val visiblePageItems: List<PageRelated> = filteredPageItems
 
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesViewModel.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesViewModel.kt
index 11c47ecbfc..d4915e548c 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesViewModel.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/NotesViewModel.kt
@@ -1,6 +1,6 @@
 /*
  * Kiwix Android
- * Copyright (c) 2020 Kiwix <android.kiwix.org>
+ * Copyright (c) 2024 Kiwix <android.kiwix.org>
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or
@@ -18,6 +18,7 @@
 
 package org.kiwix.kiwixmobile.core.page.notes.viewmodel
 
+import androidx.lifecycle.viewModelScope
 import kotlinx.coroutines.CoroutineScope
 import org.kiwix.kiwixmobile.core.dao.NotesRoomDao
 import org.kiwix.kiwixmobile.core.page.adapter.Page
@@ -44,7 +45,15 @@ class NotesViewModel @Inject constructor(
   }
 
   override fun initialState(): NotesState =
-    NotesState(emptyList(), sharedPreferenceUtil.showNotesAllBooks, zimReaderContainer.id)
+    NotesState(
+      emptyList(),
+      sharedPreferenceUtil.showNotesAllBooks,
+      zimReaderContainer.id,
+      isLoading = false
+    )
+
+  override fun loadData(state: NotesState, action: Action.LoadingData): NotesState =
+    state.copy(isLoading = action.isLoading)
 
   override fun updatePagesBasedOnFilter(state: NotesState, action: Action.Filter): NotesState =
     state.copy(searchTerm = action.searchTerm)
@@ -70,5 +79,5 @@ class NotesViewModel @Inject constructor(
     ShowDeleteNotesDialog(effects, state, pageDao, viewModelScope)
 
   override fun onItemClick(page: Page) =
-    ShowOpenNoteDialog(effects, page, zimReaderContainer)
+    ShowOpenNoteDialog(effects, actions, page, zimReaderContainer, viewModelScope)
 }
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/effects/ShowOpenNoteDialog.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/effects/ShowOpenNoteDialog.kt
index d1ce75018d..637912bfbe 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/effects/ShowOpenNoteDialog.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/viewmodel/effects/ShowOpenNoteDialog.kt
@@ -20,11 +20,14 @@ package org.kiwix.kiwixmobile.core.page.notes.viewmodel.effects
 
 import androidx.appcompat.app.AppCompatActivity
 import io.reactivex.processors.PublishProcessor
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
 import org.json.JSONArray
 import org.kiwix.kiwixmobile.core.base.SideEffect
 import org.kiwix.kiwixmobile.core.extensions.ActivityExtensions.cachedComponent
 import org.kiwix.kiwixmobile.core.page.adapter.Page
 import org.kiwix.kiwixmobile.core.page.notes.adapter.NoteListItem
+import org.kiwix.kiwixmobile.core.page.viewmodel.Action
 import org.kiwix.kiwixmobile.core.page.viewmodel.effects.OpenNote
 import org.kiwix.kiwixmobile.core.page.viewmodel.effects.OpenPage
 import org.kiwix.kiwixmobile.core.reader.ZimFileReader.Companion.CONTENT_PREFIX
@@ -41,8 +44,10 @@ import javax.inject.Inject
 
 data class ShowOpenNoteDialog(
   private val effects: PublishProcessor<SideEffect<*>>,
+  private val actions: PublishProcessor<Action>,
   private val page: Page,
-  private val zimReaderContainer: ZimReaderContainer
+  private val zimReaderContainer: ZimReaderContainer,
+  private val dialogScope: CoroutineScope
 ) : SideEffect<Unit> {
   @Inject lateinit var dialogShower: DialogShower
   override fun invokeWith(activity: AppCompatActivity) {
@@ -51,35 +56,39 @@ data class ShowOpenNoteDialog(
       ShowNoteDialog,
       { effects.offer(OpenPage(page, zimReaderContainer)) },
       {
-        val item = page as NoteListItem
-        // Check if zimFilePath is not null, and then set it in zimReaderContainer.
-        // For custom apps, we are currently using fileDescriptor, and they only have a single file in them,
-        // which is already set in zimReaderContainer, so there's no need to set it again.
-        item.zimFilePath?.let {
-          val currentZimFilePath = zimReaderContainer.zimCanonicalPath
-          val file = File(it)
-          zimReaderContainer.setZimFile(file)
-          if (zimReaderContainer.zimCanonicalPath != currentZimFilePath) {
-            // if current zim file is not the same set the main page of that zim file
-            // so that when we go back it properly loads the article, and do nothing if the
-            // zim file is same because there might be multiple tabs opened.
-            val settings = activity.getSharedPreferences(
-              SharedPreferenceUtil.PREF_KIWIX_MOBILE,
-              0
-            )
-            val editor = settings.edit()
-            val urls = JSONArray()
-            val positions = JSONArray()
-            urls.put(CONTENT_PREFIX + zimReaderContainer.mainPage)
-            positions.put(0)
-            editor.putString(TAG_CURRENT_FILE, zimReaderContainer.zimCanonicalPath)
-            editor.putString(TAG_CURRENT_ARTICLES, "$urls")
-            editor.putString(TAG_CURRENT_POSITIONS, "$positions")
-            editor.putInt(TAG_CURRENT_TAB, 0)
-            editor.apply()
+        actions.offer(Action.LoadingData(true))
+        dialogScope.launch {
+          val item = page as NoteListItem
+          // Check if zimFilePath is not null, and then set it in zimReaderContainer.
+          // For custom apps, we are currently using fileDescriptor, and they only have a single file in them,
+          // which is already set in zimReaderContainer, so there's no need to set it again.
+          item.zimFilePath?.let {
+            val currentZimFilePath = zimReaderContainer.zimCanonicalPath
+            val file = File(it)
+            zimReaderContainer.setZimFile(file)
+            if (zimReaderContainer.zimCanonicalPath != currentZimFilePath) {
+              // if current zim file is not the same set the main page of that zim file
+              // so that when we go back it properly loads the article, and do nothing if the
+              // zim file is same because there might be multiple tabs opened.
+              val settings = activity.getSharedPreferences(
+                SharedPreferenceUtil.PREF_KIWIX_MOBILE,
+                0
+              )
+              val editor = settings.edit()
+              val urls = JSONArray()
+              val positions = JSONArray()
+              urls.put(CONTENT_PREFIX + zimReaderContainer.mainPage)
+              positions.put(0)
+              editor.putString(TAG_CURRENT_FILE, zimReaderContainer.zimCanonicalPath)
+              editor.putString(TAG_CURRENT_ARTICLES, "$urls")
+              editor.putString(TAG_CURRENT_POSITIONS, "$positions")
+              editor.putInt(TAG_CURRENT_TAB, 0)
+              editor.apply()
+            }
           }
+          effects.offer(OpenNote(item.noteFilePath, item.zimUrl, item.title))
+          actions.offer(Action.LoadingData(false))
         }
-        effects.offer(OpenNote(item.noteFilePath, item.zimUrl, item.title))
       }
     )
   }
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/Action.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/Action.kt
index 428d02275b..33efc5598b 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/Action.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/Action.kt
@@ -7,7 +7,7 @@ sealed class Action {
   object ExitActionModeMenu : Action()
   object UserClickedDeleteButton : Action()
   object UserClickedDeleteSelectedPages : Action()
-
+  data class LoadingData(val isLoading: Boolean) : Action()
   data class OnItemClick(val page: Page) : Action()
   data class OnItemLongClick(val page: Page) : Action()
   data class UserClickedShowAllToggle(val isChecked: Boolean) : Action()
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageState.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageState.kt
index 05decb8746..45ab22c72e 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageState.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageState.kt
@@ -24,6 +24,7 @@ import org.kiwix.kiwixmobile.core.page.bookmark.adapter.LibkiwixBookmarkItem
 
 abstract class PageState<T : Page> {
   abstract val pageItems: List<T>
+  abstract val isLoading: Boolean
   val isInSelectionState: Boolean by lazy { pageItems.any(Page::isSelected) }
   protected val filteredPageItems: List<T> by lazy {
     pageItems.filter { showAll || it.zimId == currentZimId }
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageViewModel.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageViewModel.kt
index 95379f6c3e..ff9403d978 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageViewModel.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/page/viewmodel/PageViewModel.kt
@@ -88,8 +88,11 @@ abstract class PageViewModel<T : Page, S : PageState<T>>(
     is OnItemLongClick -> handleItemLongClick(state, action)
     is Filter -> updatePagesBasedOnFilter(state, action)
     is UpdatePages -> updatePages(state, action)
+    is Action.LoadingData -> loadData(state, action)
   }
 
+  abstract fun loadData(state: S, action: Action.LoadingData): S
+
   abstract fun updatePagesBasedOnFilter(state: S, action: Filter): S
 
   abstract fun updatePages(state: S, action: UpdatePages): S
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimFileReader.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimFileReader.kt
index 43cda59df5..d4e0fa75c2 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimFileReader.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimFileReader.kt
@@ -234,24 +234,29 @@ class ZimFileReader constructor(
 
   @Suppress("UnreachableCode", "NestedBlockDepth", "ReturnCount")
   private fun loadContent(uri: String, extension: String): InputStream? {
-    val item = getItem(uri)
-    if (compressedExtensions.any { it != extension }) {
-      item?.size?.let {
-        // Check if the item size exceeds 1 MB
-        if (it / Kb > 1024) {
-          // Retrieve direct access information for the item
-          val infoPair = getDirectAccessInfoOfItem(item, uri)
-          val file = infoPair?.filename?.let(::File)
-          // If no file found or file does not exist, return input stream from item data
-          if (infoPair == null || file == null || !file.exists()) {
-            return@loadContent ByteArrayInputStream(item.data?.data)
+    try {
+      val item = getItem(uri)
+      if (compressedExtensions.any { it != extension }) {
+        item?.size?.let {
+          // Check if the item size exceeds 1 MB
+          if (it / Kb > 1024) {
+            // Retrieve direct access information for the item
+            val infoPair = getDirectAccessInfoOfItem(item, uri)
+            val file = infoPair?.filename?.let(::File)
+            // If no file found or file does not exist, return input stream from item data
+            if (infoPair == null || file == null || !file.exists()) {
+              return@loadContent ByteArrayInputStream(item.data?.data)
+            }
+            // Return the input stream from the direct access information
+            return@loadContent getInputStreamFromDirectAccessInfo(item, file, infoPair)
           }
-          // Return the input stream from the direct access information
-          return@loadContent getInputStreamFromDirectAccessInfo(item, file, infoPair)
         }
       }
+      return loadContent(item, uri)
+    } catch (exception: Exception) {
+      Log.e("ZimFileReader", "exception caught while loading content$exception")
+      return null
     }
-    return loadContent(item, uri)
   }
 
   fun getMimeTypeFromUrl(uri: String): String? = getItem(uri)?.mimetype
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimReaderContainer.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimReaderContainer.kt
index 46027b840f..a6e95f46d2 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimReaderContainer.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/reader/ZimReaderContainer.kt
@@ -19,7 +19,9 @@ package org.kiwix.kiwixmobile.core.reader
 
 import android.content.res.AssetFileDescriptor
 import android.webkit.WebResourceResponse
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withContext
 import org.kiwix.kiwixmobile.core.extensions.isFileExist
 import org.kiwix.kiwixmobile.core.reader.ZimFileReader.Factory
 import java.io.File
@@ -35,21 +37,21 @@ class ZimReaderContainer @Inject constructor(private val zimFileReaderFactory: F
       field = value
     }
 
-  fun setZimFile(file: File?) {
+  suspend fun setZimFile(file: File?) {
     if (file?.canonicalPath == zimFileReader?.zimFile?.canonicalPath) {
       return
     }
-    zimFileReader = runBlocking {
+    zimFileReader = withContext(Dispatchers.IO) {
       if (file?.isFileExist() == true) zimFileReaderFactory.create(file)
       else null
     }
   }
 
-  fun setZimFileDescriptor(
+  suspend fun setZimFileDescriptor(
     assetFileDescriptorList: List<AssetFileDescriptor>,
     filePath: String? = null
   ) {
-    zimFileReader = runBlocking {
+    zimFileReader = withContext(Dispatchers.IO) {
       if (assetFileDescriptorList.isNotEmpty() &&
         assetFileDescriptorList[0].parcelFileDescriptor.fileDescriptor.valid()
       )
diff --git a/core/src/main/res/layout/fragment_page.xml b/core/src/main/res/layout/fragment_page.xml
index bdb365b429..6a14b36c8b 100644
--- a/core/src/main/res/layout/fragment_page.xml
+++ b/core/src/main/res/layout/fragment_page.xml
@@ -38,6 +38,17 @@
     app:layout_constraintStart_toStartOf="parent"
     app:layout_constraintTop_toBottomOf="@id/app_bar" />
 
+  <androidx.core.widget.ContentLoadingProgressBar
+    android:id="@+id/loading_zimfile_content"
+    style="?android:attr/progressBarStyleHorizontal"
+    android:layout_width="match_parent"
+    android:layout_height="@dimen/progress_view_height"
+    android:indeterminate="false"
+    android:max="100"
+    android:theme="@style/ThemeOverlay.KiwixTheme.ProgressBar"
+    android:visibility="gone"
+    app:layout_constraintTop_toBottomOf="@+id/app_bar"
+    tools:progress="70" />
   <androidx.recyclerview.widget.RecyclerView
     android:id="@+id/recycler_view"
     android:layout_width="0dp"
diff --git a/custom/src/androidTest/java/org/kiwix/kiwixmobile/custom/search/SearchFragmentTestForCustomApp.kt b/custom/src/androidTest/java/org/kiwix/kiwixmobile/custom/search/SearchFragmentTestForCustomApp.kt
index 9afff2746a..0274dc44d1 100644
--- a/custom/src/androidTest/java/org/kiwix/kiwixmobile/custom/search/SearchFragmentTestForCustomApp.kt
+++ b/custom/src/androidTest/java/org/kiwix/kiwixmobile/custom/search/SearchFragmentTestForCustomApp.kt
@@ -33,8 +33,10 @@ import androidx.test.internal.runner.junit4.statement.UiThreadStatement
 import androidx.test.platform.app.InstrumentationRegistry
 import androidx.test.rule.GrantPermissionRule
 import androidx.test.uiautomator.UiDevice
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withContext
 import okhttp3.OkHttpClient
 import okhttp3.Request
 import okhttp3.ResponseBody
@@ -111,7 +113,7 @@ class SearchFragmentTestForCustomApp {
   }
 
   @Test
-  fun searchFragment() {
+  fun searchFragment() = runBlocking {
     activityScenario.onActivity {
       customMainActivity = it
     }
@@ -251,14 +253,20 @@ class SearchFragmentTestForCustomApp {
     }
   }
 
-  private fun openZimFileInReaderWithAssetFileDescriptor(downloadingZimFile: File) {
-    getAssetFileDescriptorFromFile(downloadingZimFile)?.let(::openZimFileInReader) ?: run {
-      throw RuntimeException("Unable to get fileDescriptor from file. Original exception")
-    }
+  private suspend fun openZimFileInReaderWithAssetFileDescriptor(downloadingZimFile: File) {
+    getAssetFileDescriptorFromFile(downloadingZimFile)?.let { assetFileDescriptor ->
+      withContext(Dispatchers.IO) {
+        try {
+          openZimFileInReader(assetFileDescriptor)
+        } catch (e: Exception) {
+          throw RuntimeException("Unable to get fileDescriptor from file. Original exception", e)
+        }
+      }
+    } ?: throw RuntimeException("Unable to get fileDescriptor from file.")
   }
 
-  private fun openZimFileInReader(assetFileDescriptor: AssetFileDescriptor) {
-    UiThreadStatement.runOnUiThread {
+  private suspend fun openZimFileInReader(assetFileDescriptor: AssetFileDescriptor) {
+    withContext(Dispatchers.Main) {
       val navHostFragment: NavHostFragment =
         customMainActivity.supportFragmentManager
           .findFragmentById(
@@ -266,7 +274,9 @@ class SearchFragmentTestForCustomApp {
           ) as NavHostFragment
       val customReaderFragment =
         navHostFragment.childFragmentManager.fragments[0] as CustomReaderFragment
-      customReaderFragment.openZimFile(null, true, listOf(assetFileDescriptor))
+      withContext(Dispatchers.IO) {
+        customReaderFragment.openZimFile(null, true, listOf(assetFileDescriptor))
+      }
     }
   }
 
diff --git a/custom/src/main/java/org/kiwix/kiwixmobile/custom/main/CustomReaderFragment.kt b/custom/src/main/java/org/kiwix/kiwixmobile/custom/main/CustomReaderFragment.kt
index 9321cd0858..fd3f6239bd 100644
--- a/custom/src/main/java/org/kiwix/kiwixmobile/custom/main/CustomReaderFragment.kt
+++ b/custom/src/main/java/org/kiwix/kiwixmobile/custom/main/CustomReaderFragment.kt
@@ -29,7 +29,11 @@ import android.widget.ImageView
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.widget.Toolbar
 import androidx.drawerlayout.widget.DrawerLayout
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.lifecycleScope
+import androidx.lifecycle.repeatOnLifecycle
 import androidx.navigation.fragment.findNavController
+import kotlinx.coroutines.launch
 import org.kiwix.kiwixmobile.core.R.dimen
 import org.kiwix.kiwixmobile.core.base.BaseActivity
 import org.kiwix.kiwixmobile.core.extensions.getResizedDrawable
@@ -68,23 +72,26 @@ class CustomReaderFragment : CoreReaderFragment() {
     if (enforcedLanguage()) {
       return
     }
-
-    if (isAdded) {
-      setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED)
-      if (BuildConfig.DISABLE_SIDEBAR) {
-        val toolbarToc = activity?.findViewById<ImageView>(R.id.bottom_toolbar_toc)
-        toolbarToc?.isEnabled = false
-      }
-      with(activity as AppCompatActivity) {
-        supportActionBar?.setDisplayHomeAsUpEnabled(true)
-        toolbar?.let(::setUpDrawerToggle)
-      }
-      loadPageFromNavigationArguments()
-      if (BuildConfig.DISABLE_EXTERNAL_LINK) {
-        // If "external links" are disabled in a custom app,
-        // this sets the shared preference to not show the external link popup
-        // when opening external links.
-        sharedPreferenceUtil?.putPrefExternalLinkPopup(false)
+    lifecycleScope.launch {
+      viewLifecycleOwner.repeatOnLifecycle(Lifecycle.State.STARTED) {
+        if (isAdded) {
+          setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED)
+          if (BuildConfig.DISABLE_SIDEBAR) {
+            val toolbarToc = activity?.findViewById<ImageView>(R.id.bottom_toolbar_toc)
+            toolbarToc?.isEnabled = false
+          }
+          with(activity as AppCompatActivity) {
+            supportActionBar?.setDisplayHomeAsUpEnabled(true)
+            toolbar?.let(::setUpDrawerToggle)
+          }
+          loadPageFromNavigationArguments()
+          if (BuildConfig.DISABLE_EXTERNAL_LINK) {
+            // If "external links" are disabled in a custom app,
+            // this sets the shared preference to not show the external link popup
+            // when opening external links.
+            sharedPreferenceUtil?.putPrefExternalLinkPopup(false)
+          }
+        }
       }
     }
   }
@@ -129,7 +136,7 @@ class CustomReaderFragment : CoreReaderFragment() {
     super.setTabSwitcherVisibility(visibility)
   }
 
-  private fun loadPageFromNavigationArguments() {
+  private suspend fun loadPageFromNavigationArguments() {
     val args = CustomReaderFragmentArgs.fromBundle(requireArguments())
     if (args.pageUrl.isNotEmpty()) {
       loadUrlWithCurrentWebview(args.pageUrl)
@@ -148,7 +155,7 @@ class CustomReaderFragment : CoreReaderFragment() {
    * due to invalid or corrupted data. In this case, it opens the homepage of the zim file,
    * as custom apps always have the zim file available.
    */
-  override fun restoreViewStateOnInvalidJSON() {
+  override suspend fun restoreViewStateOnInvalidJSON() {
     openHomeScreen()
   }
 
@@ -179,30 +186,32 @@ class CustomReaderFragment : CoreReaderFragment() {
   private fun openObbOrZim() {
     customFileValidator.validate(
       onFilesFound = {
-        when (it) {
-          is ValidationState.HasFile -> {
-            if (it.assetFileDescriptorList.isNotEmpty()) {
-              openZimFile(null, true, it.assetFileDescriptorList)
-            } else {
-              openZimFile(it.file, true)
+        lifecycleScope.launch {
+          when (it) {
+            is ValidationState.HasFile -> {
+              if (it.assetFileDescriptorList.isNotEmpty()) {
+                openZimFile(null, true, it.assetFileDescriptorList)
+              } else {
+                openZimFile(it.file, true)
+              }
+              // Save book in the database to display it in `ZimHostFragment`.
+              zimReaderContainer?.zimFileReader?.let { zimFileReader ->
+                // Check if the file is not null. If the file is null,
+                // it means we have created zimFileReader with a fileDescriptor,
+                // so we create a demo file to save it in the database for display on the `ZimHostFragment`.
+                val file = it.file ?: createDemoFile()
+                val bookOnDisk = BookOnDisk(file, zimFileReader)
+                repositoryActions?.saveBook(bookOnDisk)
+              }
             }
-            // Save book in the database to display it in `ZimHostFragment`.
-            zimReaderContainer?.zimFileReader?.let { zimFileReader ->
-              // Check if the file is not null. If the file is null,
-              // it means we have created zimFileReader with a fileDescriptor,
-              // so we create a demo file to save it in the database for display on the `ZimHostFragment`.
-              val file = it.file ?: createDemoFile()
-              val bookOnDisk = BookOnDisk(file, zimFileReader)
-              repositoryActions?.saveBook(bookOnDisk)
+
+            is ValidationState.HasBothFiles -> {
+              it.zimFile.delete()
+              openZimFile(it.obbFile, true)
             }
-          }
 
-          is ValidationState.HasBothFiles -> {
-            it.zimFile.delete()
-            openZimFile(it.obbFile, true)
+            else -> {}
           }
-
-          else -> {}
         }
       },
       onNoFilesFound = {