diff --git a/app/src/main/java/eu/kanade/tachiyomi/data/database/models/MangaImpl.kt b/app/src/main/java/eu/kanade/tachiyomi/data/database/models/MangaImpl.kt
index 82dfcefd36..2c229a6486 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/data/database/models/MangaImpl.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/data/database/models/MangaImpl.kt
@@ -64,7 +64,8 @@ open class MangaImpl : Manga {
     }
 
     override fun hashCode(): Int {
-        return url.hashCode()
+        if (::url.isInitialized) return url.hashCode()
+        else return (id ?: 0L).hashCode()
     }
 
     companion object {
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryController.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryController.kt
index 43b63a6970..3c181fb353 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryController.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryController.kt
@@ -163,7 +163,7 @@ class LibraryController(
                 activeCategory = order
                 if (presenter.categories.size > 1 && dy != 0) {
                     val headerItem = getHeader() ?: return
-                    val view = fast_scroller.getChildAt(0) ?: return
+                    val view = fast_scroller?.getChildAt(0) ?: return
                     val index = adapter.headerItems.indexOf(headerItem)
                     textAnim?.cancel()
                     textAnim = text_view_m.animate().alpha(0f).setDuration(250L).setStartDelay(2000)
@@ -186,12 +186,12 @@ class LibraryController(
             when (newState) {
                 RecyclerView.SCROLL_STATE_DRAGGING -> {
                     scrollAnim?.cancel()
-                    if (fast_scroller.translationX != 0f) {
-                        fast_scroller.show()
+                    if (fast_scroller?.translationX != 0f) {
+                        fast_scroller?.show()
                     }
                 }
                 RecyclerView.SCROLL_STATE_IDLE -> {
-                    scrollAnim = fast_scroller.hide()
+                    scrollAnim = fast_scroller?.hide()
                 }
             }
         }
@@ -299,7 +299,7 @@ class LibraryController(
         activity!!.theme.resolveAttribute(R.attr.actionBarTintColor, tv, true)
         swipe_refresh.setStyle()
         scrollViewWith(recycler, swipeRefreshLayout = swipe_refresh, afterInsets = { insets ->
-            fast_scroller.updateLayoutParams<ViewGroup.MarginLayoutParams> {
+            fast_scroller?.updateLayoutParams<ViewGroup.MarginLayoutParams> {
                 topMargin = insets.systemWindowInsetTop
             }
         })
@@ -405,11 +405,11 @@ class LibraryController(
 
     fun updateShowScrollbar(show: Boolean) {
         alwaysShowScroller = show
-        fast_scroller.setBackground(!show)
+        fast_scroller?.setBackground(!show)
         if (libraryLayout == 0) reattachAdapter()
         scrollAnim?.cancel()
-        if (show) fast_scroller.translationX = 0f
-        else scrollAnim = fast_scroller.hide()
+        if (show) fast_scroller?.translationX = 0f
+        else scrollAnim = fast_scroller?.hide()
         setRecyclerLayout()
     }
 
@@ -503,9 +503,9 @@ class LibraryController(
         if (justStarted && freshStart) {
             scrollToHeader(activeCategory)
             if (!alwaysShowScroller) {
-                fast_scroller.show(false)
+                fast_scroller?.show(false)
                 view?.post {
-                    scrollAnim = fast_scroller.hide(2000)
+                    scrollAnim = fast_scroller?.hide(2000)
                 }
             }
         }
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/main/SearchActivity.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/main/SearchActivity.kt
index 1846133fe0..556074ac34 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/main/SearchActivity.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/main/SearchActivity.kt
@@ -6,8 +6,8 @@ import android.os.Bundle
 import com.bluelinelabs.conductor.Controller
 import eu.kanade.tachiyomi.data.notification.NotificationReceiver
 import eu.kanade.tachiyomi.ui.base.controller.DialogController
-import eu.kanade.tachiyomi.ui.source.global_search.SourceSearchController
 import eu.kanade.tachiyomi.ui.security.SecureActivityDelegate
+import eu.kanade.tachiyomi.ui.source.global_search.SourceSearchController
 import eu.kanade.tachiyomi.util.view.gone
 import eu.kanade.tachiyomi.util.view.withFadeTransaction
 import kotlinx.android.synthetic.main.main_activity.*
@@ -16,8 +16,8 @@ class SearchActivity : MainActivity() {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        toolbar.navigationIcon = drawerArrow
-        toolbar.setNavigationOnClickListener {
+        toolbar?.navigationIcon = drawerArrow
+        toolbar?.setNavigationOnClickListener {
             popToRoot()
         }
     }
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaDetailsPresenter.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaDetailsPresenter.kt
index d424a5561c..321fdce21b 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaDetailsPresenter.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaDetailsPresenter.kt
@@ -477,7 +477,9 @@ class MangaDetailsPresenter(
                 updateChapters()
                 withContext(Dispatchers.Main) { controller.updateChapters(this@MangaDetailsPresenter.chapters) }
             } catch (e: java.lang.Exception) {
-                controller.showError(trimException(e))
+                withContext(Dispatchers.Main) {
+                    controller.showError(trimException(e))
+                }
             }
         }
     }
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerViewer.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerViewer.kt
index 001f043624..0a9b6bd9e8 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerViewer.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerViewer.kt
@@ -140,10 +140,10 @@ abstract class PagerViewer(val activity: ReaderActivity) : BaseViewer {
      * activity of the change and requests the preload of the next chapter if this is the last page.
      */
     private fun onReaderPageSelected(page: ReaderPage) {
-        val pages = page.chapter.pages!! // Won't be null because it's the loaded chapter
-        Timber.d("onReaderPageSelected: ${page.number}/${pages.size}")
         activity.onPageSelected(page)
 
+        val pages = page.chapter.pages ?: return
+        Timber.d("onReaderPageSelected: ${page.number}/${pages.size}")
         // Preload next chapter once we're within the last 3 pages of the current chapter
         val inPreloadRange = pages.size - page.number < 3
         if (inPreloadRange) {
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/recents/RecentsController.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/recents/RecentsController.kt
index e1686872a1..48bb9001f9 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/recents/RecentsController.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/recents/RecentsController.kt
@@ -253,6 +253,7 @@ class RecentsController(bundle: Bundle? = null) : BaseController(bundle),
     fun refresh() = presenter.getRecents()
 
     fun showLists(recents: List<RecentMangaItem>) {
+        if (view == null) return
         swipe_refresh.isRefreshing = LibraryUpdateService.isRunning()
         adapter.updateItems(recents)
         adapter.removeAllScrollableHeaders()