diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryScreenModel.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryScreenModel.kt
index 147026737..0aa43e980 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryScreenModel.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryScreenModel.kt
@@ -442,11 +442,9 @@ class LibraryScreenModel(
     ): Map<Long, Long?> {
         if (favorites.isEmpty()) return emptyMap()
 
-        val chapterDurationsByMangaId = getReadDurationEntriesByMangaIds.await(
-            favorites.map { it.id },
-        )
-            .groupBy { it.mangaId }
-            .mapValues { (_, entries) -> entries.map { it.readDuration } }
+        val chapterDurationsByMangaId = favorites.associate { item ->
+            item.id to getReadDurationEntriesByMangaIds.await(item.id).map { it.readDuration }
+        }
         val globalAverageChapterDurationMs = calculateAverageChapterDurationMs(
             chapterDurationsByMangaId.values.flatten(),
         )
diff --git a/domain/src/main/java/tachiyomi/domain/history/interactor/GetReadDurationEntriesByMangaIds.kt b/domain/src/main/java/tachiyomi/domain/history/interactor/GetReadDurationEntriesByMangaIds.kt
index 2857bccd2..50d197f00 100644
--- a/domain/src/main/java/tachiyomi/domain/history/interactor/GetReadDurationEntriesByMangaIds.kt
+++ b/domain/src/main/java/tachiyomi/domain/history/interactor/GetReadDurationEntriesByMangaIds.kt
@@ -6,9 +6,11 @@ import tachiyomi.domain.history.repository.HistoryRepository
 class GetReadDurationEntriesByMangaIds(
     private val repository: HistoryRepository,
 ) {
+    suspend fun await(mangaId: Long): List<History> {
+        return repository.getHistoryByMangaId(mangaId)
+    }
+
     suspend fun await(mangaIds: List<Long>): List<History> {
-        return mangaIds.flatMap { mangaId ->
-            repository.getHistoryByMangaId(mangaId)
-        }
+        return mangaIds.flatMap(::await)
     }
 }