diff --git a/app/src/main/java/eu/kanade/presentation/manga/DuplicateMangaDialog.kt b/app/src/main/java/eu/kanade/presentation/manga/DuplicateMangaDialog.kt
index e3ff20ad2..859bb5820 100644
--- a/app/src/main/java/eu/kanade/presentation/manga/DuplicateMangaDialog.kt
+++ b/app/src/main/java/eu/kanade/presentation/manga/DuplicateMangaDialog.kt
@@ -57,3 +57,60 @@ fun DuplicateMangaDialog(
         },
     )
 }
+
+// KMK -->
+@Composable
+fun AllowDuplicateDialog(
+    onDismissRequest: () -> Unit,
+    onAllowDuplicate: () -> Unit,
+    onSkipDuplicate: () -> Unit,
+    onOpenManga: () -> Unit = { },
+) {
+    AlertDialog(
+        onDismissRequest = onDismissRequest,
+        dismissButton = {
+            TextButton(onClick = onDismissRequest) {
+                Text(text = stringResource(MR.strings.action_cancel))
+            }
+        },
+        title = {
+            Text(text = stringResource(MR.strings.are_you_sure))
+        },
+        text = {
+            Text(text = stringResource(MR.strings.confirm_add_duplicate_manga))
+        },
+        confirmButton = {
+            FlowRow(
+                horizontalArrangement = Arrangement.spacedBy(MaterialTheme.padding.extraSmall),
+            ) {
+                TextButton(
+                    onClick = {
+                        onDismissRequest()
+                        onOpenManga()
+                    },
+                ) {
+                    Text(text = stringResource(MR.strings.action_show_manga))
+                }
+
+                TextButton(
+                    onClick = {
+                        onDismissRequest()
+                        onSkipDuplicate()
+                    },
+                ) {
+                    Text(text = stringResource(MR.strings.action_skip_duplicate_manga))
+                }
+
+                TextButton(
+                    onClick = {
+                        onDismissRequest()
+                        onAllowDuplicate()
+                    },
+                ) {
+                    Text(text = stringResource(MR.strings.action_allow_duplicate_manga))
+                }
+            }
+        },
+    )
+}
+// KMK <--
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreen.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreen.kt
index 76f5dbcfd..45bd99013 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreen.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreen.kt
@@ -45,6 +45,7 @@ import eu.kanade.presentation.browse.components.SavedSearchCreateDialog
 import eu.kanade.presentation.browse.components.SavedSearchDeleteDialog
 import eu.kanade.presentation.browse.components.SelectionToolbar
 import eu.kanade.presentation.category.components.ChangeCategoryDialog
+import eu.kanade.presentation.manga.AllowDuplicateDialog
 import eu.kanade.presentation.manga.DuplicateMangaDialog
 import eu.kanade.presentation.util.AssistContentScreen
 import eu.kanade.presentation.util.Screen
@@ -395,6 +396,17 @@ data class BrowseSourceScreen(
                     },
                 )
             }
+            is BrowseSourceScreenModel.Dialog.AllowDuplicate -> {
+                AllowDuplicateDialog(
+                    onDismissRequest = onDismissRequest,
+                    onAllowDuplicate = {
+                        screenModel.addFavoriteDuplicate()
+                    },
+                    onSkipDuplicate = {
+                        screenModel.addFavoriteDuplicate(skipDuplicate = true)
+                    },
+                )
+            }
             // KMK <--
             else -> {}
         }
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreenModel.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreenModel.kt
index 59a7f33c2..b19ffbde4 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreenModel.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreenModel.kt
@@ -477,7 +477,16 @@ open class BrowseSourceScreenModel(
 
     fun addFavorite() {
         screenModelScope.launch {
-            val mangaList = state.value.selection
+            if (hasDuplicateLibraryMangas(state.value.selection))
+                setDialog(Dialog.AllowDuplicate)
+            else
+                addFavoriteDuplicate()
+        }
+    }
+
+    fun addFavoriteDuplicate(skipDuplicate: Boolean = false) {
+        screenModelScope.launch {
+            val mangaList = if (skipDuplicate) getNotDuplicateLibraryMangas() else state.value.selection
             val categories = getCategories()
             val defaultCategoryId = libraryPreferences.defaultCategory().get()
             val defaultCategory = categories.find { it.id == defaultCategoryId.toLong() }
@@ -574,6 +583,18 @@ open class BrowseSourceScreenModel(
         val common = mangaCategories.reduce { set1, set2 -> set1.intersect(set2) }
         return mangaCategories.flatten().distinct().subtract(common)
     }
+
+    private suspend fun getNotDuplicateLibraryMangas(): List<Manga> {
+        return state.value.selection.filterNot { manga ->
+            getDuplicateLibraryManga.await(manga).isNotEmpty()
+        }
+    }
+
+    private suspend fun hasDuplicateLibraryMangas(mangas: List<Manga>): Boolean {
+        return mangas.fastAny { manga ->
+            getDuplicateLibraryManga.await(manga).isNotEmpty()
+        }
+    }
     // KMK <--
 
     sealed interface Dialog {
@@ -595,6 +616,7 @@ open class BrowseSourceScreenModel(
             val mangas: List<Manga>,
             val initialSelection: ImmutableList<CheckboxState<Category>>,
         ) : Dialog
+        data object AllowDuplicate : Dialog
         // KMK <--
     }
 
diff --git a/i18n/src/commonMain/resources/MR/base/strings.xml b/i18n/src/commonMain/resources/MR/base/strings.xml
index 78ef237d9..3d3cc7866 100644
--- a/i18n/src/commonMain/resources/MR/base/strings.xml
+++ b/i18n/src/commonMain/resources/MR/base/strings.xml
@@ -689,6 +689,8 @@
     <string name="source_not_installed">Source not installed: %1$s</string>
     <string name="snack_add_to_library">Add to library?</string>
     <string name="description_placeholder">No description</string>
+    <string name="action_allow_duplicate_manga">Allow duplicate</string>
+    <string name="action_skip_duplicate_manga">Skip duplicate</string>
 
     <!-- Manga chapters -->
     <string name="display_mode_chapter">Chapter %1$s</string>