Fix popular not working in M+. (#13953)

src/all/mangaplus/build.gradle

@@ -6,7 +6,7 @@ ext {
     extName = 'MANGA Plus by SHUEISHA'
     pkgNameSuffix = 'all.mangaplus'
     extClass = '.MangaPlusFactory'
-    extVersionCode = 38
+    extVersionCode = 39
 }
 
 apply from: "$rootDir/common.gradle"

src/all/mangaplus/src/eu/kanade/tachiyomi/extension/all/mangaplus/MangaPlus.kt

@@ -199,7 +199,7 @@ class MangaPlus(
             .filter { it.language == langCode }
             .filter { title ->
                 title.name.contains(filter, ignoreCase = true) ||
-                    title.author.contains(filter, ignoreCase = true)
+                    title.author.orEmpty().contains(filter, ignoreCase = true)
             }
 
         val mangas = titleList!!.map(Title::toSManga)

src/all/mangaplus/src/eu/kanade/tachiyomi/extension/all/mangaplus/MangaPlusDto.kt

@@ -56,7 +56,7 @@ data class WebHomeViewV3(val groups: List<UpdatedTitleV2Group> = emptyList())
 data class TitleDetailView(
     val title: Title,
     val titleImageUrl: String,
-    val overview: String,
+    val overview: String? = null,
     val backgroundImageUrl: String,
     val nextTimeStamp: Int = 0,
     val viewingPeriodDescription: String = "",
@@ -92,7 +92,7 @@ data class TitleDetailView(
         )
 
     fun toSManga(): SManga = title.toSManga().apply {
-        description = overview + "\n\n" + viewingPeriodDescription
+        description = (overview.orEmpty() + "\n\n" + viewingPeriodDescription).trim()
         status = if (isCompleted) SManga.COMPLETED else SManga.ONGOING
         genre = genres.joinToString()
     }
@@ -114,7 +114,7 @@ data class MangaViewer(
 data class Title(
     val titleId: Int,
     val name: String,
-    val author: String,
+    val author: String? = null,
     val portraitImageUrl: String,
     val landscapeImageUrl: String,
     val viewCount: Int = 0,
@@ -123,7 +123,7 @@ data class Title(
 
     fun toSManga(): SManga = SManga.create().apply {
         title = name
-        author = this@Title.author.replace(" / ", ", ")
+        author = this@Title.author?.replace(" / ", ", ")
         artist = author
         thumbnail_url = portraitImageUrl
         url = "#/titles/$titleId"