diff --git a/src/all/mangadex/build.gradle b/src/all/mangadex/build.gradle
index 79d24b2e7..86898a5b2 100644
--- a/src/all/mangadex/build.gradle
+++ b/src/all/mangadex/build.gradle
@@ -5,8 +5,8 @@ ext {
     appName = 'Tachiyomi: MangaDex'
     pkgNameSuffix = 'all.mangadex'
     extClass = '.MangadexFactory'
-    extVersionCode = 38
-    extVersionSuffix = 38
+    extVersionCode = 39
+    extVersionSuffix = 39
     libVersion = '1.2'
 }
 
diff --git a/src/all/mangadex/src/eu/kanade/tachiyomi/extension/all/mangadex/Mangadex.kt b/src/all/mangadex/src/eu/kanade/tachiyomi/extension/all/mangadex/Mangadex.kt
index f98785037..769df1342 100644
--- a/src/all/mangadex/src/eu/kanade/tachiyomi/extension/all/mangadex/Mangadex.kt
+++ b/src/all/mangadex/src/eu/kanade/tachiyomi/extension/all/mangadex/Mangadex.kt
@@ -13,10 +13,7 @@ import eu.kanade.tachiyomi.network.asObservableSuccess
 import eu.kanade.tachiyomi.source.ConfigurableSource
 import eu.kanade.tachiyomi.source.model.*
 import eu.kanade.tachiyomi.source.online.ParsedHttpSource
-import okhttp3.HttpUrl
-import okhttp3.OkHttpClient
-import okhttp3.Request
-import okhttp3.Response
+import okhttp3.*
 import org.jsoup.Jsoup
 import org.jsoup.nodes.Document
 import org.jsoup.nodes.Element
@@ -53,6 +50,10 @@ open class Mangadex(override val lang: String, private val internalLang: String,
                 chain.proceed(newReq)
             }.build()!!
 
+    override fun headersBuilder() = Headers.Builder().apply {
+        add("User-Agent", "Tachiyomi Mozilla/5.0 (Windows NT 6.3; WOW64)")
+    }
+
     private fun cookiesHeader(r18Toggle: Int, langCode: Int): String {
         val cookies = mutableMapOf<String, String>()
         cookies["mangadex_h_toggle"] = r18Toggle.toString()
@@ -414,7 +415,7 @@ open class Mangadex(override val lang: String, private val internalLang: String,
     private class TextField(name: String, val key: String) : Filter.Text(name)
     private class Genre(val id: String, name: String) : Filter.TriState(name)
     private class GenreList(genres: List<Genre>) : Filter.Group<Genre>("Genres", genres)
-    private class R18 : Filter.Select<String>("R18+", arrayOf("Default","Show all", "Show only", "Show none"))
+    private class R18 : Filter.Select<String>("R18+", arrayOf("Default", "Show all", "Show only", "Show none"))
     private class Demographic : Filter.Select<String>("Demographic", arrayOf("All", "Shounen", "Shoujo", "Seinen", "Josei"))
     private class OriginalLanguage : Filter.Select<String>("Original Language", SOURCE_LANG_LIST.map { it -> it.first }.toTypedArray())
 
@@ -427,48 +428,48 @@ open class Mangadex(override val lang: String, private val internalLang: String,
             GenreList(getGenreList())
     )
 
-    private fun getGenreList() =listOf(
-                Genre("1", "4-koma"),
-                Genre("2", "Action"),
-                Genre("3", "Adventure"),
-                Genre("4", "Award Winning"),
-                Genre("5", "Comedy"),
-                Genre("6", "Cooking"),
-                Genre("7", "Doujinshi"),
-                Genre("8", "Drama"),
-                Genre("9", "Ecchi"),
-                Genre("10", "Fantasy"),
-                Genre("11", "Gender Bender"),
-                Genre("12", "Harem"),
-                Genre("13", "Historical"),
-                Genre("14", "Horror"),
-                Genre("15", "Josei"),
-                Genre("16", "Martial Arts"),
-                Genre("17", "Mecha"),
-                Genre("18", "Medical"),
-                Genre("19", "Music"),
-                Genre("20", "Mystery"),
-                Genre("21", "Oneshot"),
-                Genre("22", "Psychological"),
-                Genre("23", "Romance"),
-                Genre("24", "School Life"),
-                Genre("25", "Sci-Fi"),
-                Genre("26", "Seinen"),
-                Genre("27", "Shoujo"),
-                Genre("28", "Shoujo Ai"),
-                Genre("29", "Shounen"),
-                Genre("30", "Shounen Ai"),
-                Genre("31", "Slice of Life"),
-                Genre("32", "Smut"),
-                Genre("33", "Sports"),
-                Genre("34", "Supernatural"),
-                Genre("35", "Tragedy"),
-                Genre("36", "Webtoon"),
-                Genre("37", "Yaoi"),
-                Genre("38", "Yuri"),
-                Genre("39", "[no chapters]"),
-                Genre("40", "Game"),
-                Genre("41", "Isekai"))
+    private fun getGenreList() = listOf(
+            Genre("1", "4-koma"),
+            Genre("2", "Action"),
+            Genre("3", "Adventure"),
+            Genre("4", "Award Winning"),
+            Genre("5", "Comedy"),
+            Genre("6", "Cooking"),
+            Genre("7", "Doujinshi"),
+            Genre("8", "Drama"),
+            Genre("9", "Ecchi"),
+            Genre("10", "Fantasy"),
+            Genre("11", "Gender Bender"),
+            Genre("12", "Harem"),
+            Genre("13", "Historical"),
+            Genre("14", "Horror"),
+            Genre("15", "Josei"),
+            Genre("16", "Martial Arts"),
+            Genre("17", "Mecha"),
+            Genre("18", "Medical"),
+            Genre("19", "Music"),
+            Genre("20", "Mystery"),
+            Genre("21", "Oneshot"),
+            Genre("22", "Psychological"),
+            Genre("23", "Romance"),
+            Genre("24", "School Life"),
+            Genre("25", "Sci-Fi"),
+            Genre("26", "Seinen"),
+            Genre("27", "Shoujo"),
+            Genre("28", "Shoujo Ai"),
+            Genre("29", "Shounen"),
+            Genre("30", "Shounen Ai"),
+            Genre("31", "Slice of Life"),
+            Genre("32", "Smut"),
+            Genre("33", "Sports"),
+            Genre("34", "Supernatural"),
+            Genre("35", "Tragedy"),
+            Genre("36", "Webtoon"),
+            Genre("37", "Yaoi"),
+            Genre("38", "Yuri"),
+            Genre("39", "[no chapters]"),
+            Genre("40", "Game"),
+            Genre("41", "Isekai"))
 
     companion object {
         private val WHITESPACE_REGEX = "\\s".toRegex()