优化

app/src/main/java/io/legado/app/model/webBook/BookContent.kt

@@ -120,7 +120,7 @@ object BookContent {
         Debug.log(bookSource.bookSourceUrl, "└${bookChapter.title}")
         Debug.log(bookSource.bookSourceUrl, "┌获取正文内容")
         Debug.log(bookSource.bookSourceUrl, "└\n$contentStr")
-        if (contentStr.isBlank()) {
+        if (!bookChapter.isVolume && contentStr.isBlank()) {
             throw ContentEmptyException("内容为空")
         }
         if (needSave) {