diff --git a/app/src/main/java/org/kiwix/kiwixmobile/intro/CustomPageIndicator.kt b/app/src/main/java/org/kiwix/kiwixmobile/intro/CustomPageIndicator.kt
index cc5b7baf0..4a35eda6e 100644
--- a/app/src/main/java/org/kiwix/kiwixmobile/intro/CustomPageIndicator.kt
+++ b/app/src/main/java/org/kiwix/kiwixmobile/intro/CustomPageIndicator.kt
@@ -560,6 +560,7 @@ class CustomPageIndicator @JvmOverloads constructor(
   /**
    * A [ValueAnimator] that starts once a given predicate returns true.
    */
+  @Suppress("UnnecessaryAbstractClass")
   abstract inner class PendingStartAnimator(private var predicate: StartPredicate) :
     ValueAnimator() {
     private var hasStarted = false
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/CoreApp.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/CoreApp.kt
index e106fc0ec..f3d5d2fa2 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/CoreApp.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/CoreApp.kt
@@ -32,6 +32,7 @@ import org.kiwix.kiwixmobile.core.downloader.DownloadMonitor
 import org.kiwix.kiwixmobile.core.utils.files.FileLogger
 import javax.inject.Inject
 
+@Suppress("UnnecessaryAbstractClass")
 abstract class CoreApp : Application() {
   companion object {
     @JvmStatic
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/base/BasePresenter.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/base/BasePresenter.kt
index b3e546921..bb82216ae 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/base/BasePresenter.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/base/BasePresenter.kt
@@ -24,6 +24,7 @@ import org.kiwix.kiwixmobile.core.base.BaseContract.View
 /**
  * All presenters should inherit from this presenter.
  */
+@Suppress("UnnecessaryAbstractClass")
 abstract class BasePresenter<T : View<*>?> : Presenter<T> {
   @JvmField val compositeDisposable = CompositeDisposable()
   @JvmField var view: T? = null
diff --git a/core/src/main/java/org/kiwix/kiwixmobile/core/help/HelpFragment.kt b/core/src/main/java/org/kiwix/kiwixmobile/core/help/HelpFragment.kt
index 6a04a5104..3db5702af 100644
--- a/core/src/main/java/org/kiwix/kiwixmobile/core/help/HelpFragment.kt
+++ b/core/src/main/java/org/kiwix/kiwixmobile/core/help/HelpFragment.kt
@@ -40,6 +40,7 @@ import org.kiwix.kiwixmobile.core.main.CoreMainActivity
 import org.kiwix.kiwixmobile.core.utils.CONTACT_EMAIL_ADDRESS
 import org.kiwix.kiwixmobile.core.utils.LanguageUtils.Companion.getCurrentLocale
 
+@Suppress("UnnecessaryAbstractClass")
 abstract class HelpFragment : BaseFragment() {
   private var fragmentHelpBinding: FragmentHelpBinding? = null
   protected open fun rawTitleDescriptionMap(): List<Pair<Int, Int>> = emptyList()
diff --git a/custom/src/main/java/org/kiwix/kiwixmobile/custom/download/CustomDownloadFragment.kt b/custom/src/main/java/org/kiwix/kiwixmobile/custom/download/CustomDownloadFragment.kt
index 07562c3a3..c72e240c7 100644
--- a/custom/src/main/java/org/kiwix/kiwixmobile/custom/download/CustomDownloadFragment.kt
+++ b/custom/src/main/java/org/kiwix/kiwixmobile/custom/download/CustomDownloadFragment.kt
@@ -100,25 +100,28 @@ class CustomDownloadFragment : BaseFragment(), FragmentActivityExtensions {
     activity?.finish()
   }
 
-  private fun render(state: State) {
+  private fun render(state: State): Unit? {
     return when (state) {
       DownloadRequired ->
         fragmentCustomDownloadBinding?.cdViewAnimator?.setDistinctDisplayedChild(0)
+
       is DownloadInProgress -> {
         fragmentCustomDownloadBinding?.cdViewAnimator?.setDistinctDisplayedChild(1)
-        render(state.downloads[0])
+        showDownloadingProgress(state.downloads[0])
       }
+
       is DownloadFailed -> {
         fragmentCustomDownloadBinding?.cdViewAnimator?.setDistinctDisplayedChild(2)
         fragmentCustomDownloadBinding?.customDownloadError?.cdErrorText?.text =
           context?.let(state.downloadState::toReadableState)
       }
+
       DownloadComplete ->
         fragmentCustomDownloadBinding?.cdViewAnimator?.setDistinctDisplayedChild(3)
-    }!!
+    }
   }
 
-  private fun render(downloadItem: DownloadItem) {
+  private fun showDownloadingProgress(downloadItem: DownloadItem) {
     fragmentCustomDownloadBinding?.customDownloadInProgress?.apply {
       cdDownloadState.text = downloadItem.readableEta
       cdEta.text = context?.let(downloadItem.downloadState::toReadableState)