diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceController.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceController.kt
index 732fa22b32..31a1108432 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceController.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceController.kt
@@ -47,7 +47,6 @@ import eu.kanade.tachiyomi.util.view.snack
 import eu.kanade.tachiyomi.util.view.visible
 import eu.kanade.tachiyomi.widget.AutofitRecyclerView
 import eu.kanade.tachiyomi.widget.EmptyView
-import kotlinx.android.synthetic.main.main_activity.root_fab
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.flow.drop
 import kotlinx.coroutines.flow.filter
@@ -87,6 +86,7 @@ open class BrowseSourceController(bundle: Bundle) :
      */
     private var adapter: FlexibleAdapter<IFlexible<*>>? = null
 
+    private var actionFab: ExtendedFloatingActionButton? = null
     private var actionFabScrollListener: RecyclerView.OnScrollListener? = null
 
     /**
@@ -167,21 +167,27 @@ open class BrowseSourceController(bundle: Bundle) :
         filterSheet?.setFilters(presenter.filterItems)
 
         // TODO: [ExtendedFloatingActionButton] hide/show methods don't work properly
-        filterSheet?.setOnShowListener { activity!!.root_fab.gone() }
-        filterSheet?.setOnDismissListener { activity!!.root_fab.visible() }
+        filterSheet?.setOnShowListener { actionFab?.gone() }
+        filterSheet?.setOnDismissListener { actionFab?.visible() }
 
-        activity!!.root_fab.setOnClickListener { filterSheet?.show() }
+        actionFab?.setOnClickListener { filterSheet?.show() }
 
-        activity!!.root_fab.visible()
+        actionFab?.visible()
     }
 
     override fun configureFab(fab: ExtendedFloatingActionButton) {
+        actionFab = fab
+
+        // Controlled by initFilterSheet()
+        fab.gone()
+
         fab.setText(R.string.action_filter)
         fab.setIconResource(R.drawable.ic_filter_list_24dp)
     }
 
     override fun cleanupFab(fab: ExtendedFloatingActionButton) {
         actionFabScrollListener?.let { recycler?.removeOnScrollListener(it) }
+        actionFab = null
     }
 
     override fun onDestroyView(view: View) {
@@ -190,7 +196,6 @@ open class BrowseSourceController(bundle: Bundle) :
         adapter = null
         snack = null
         recycler = null
-        activity!!.root_fab.gone()
         super.onDestroyView(view)
     }
 
@@ -242,7 +247,7 @@ open class BrowseSourceController(bundle: Bundle) :
             )
             recycler.clipToPadding = false
 
-            activity!!.root_fab.shrinkOnScroll(recycler)
+            actionFab?.shrinkOnScroll(recycler)
         }
 
         recycler.setHasFixedSize(true)
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/category/CategoryController.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/category/CategoryController.kt
index 8eef66a212..5a5c27928c 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/category/CategoryController.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/category/CategoryController.kt
@@ -20,11 +20,8 @@ import eu.kanade.tachiyomi.databinding.CategoriesControllerBinding
 import eu.kanade.tachiyomi.ui.base.controller.FabController
 import eu.kanade.tachiyomi.ui.base.controller.NucleusController
 import eu.kanade.tachiyomi.util.system.toast
-import eu.kanade.tachiyomi.util.view.gone
 import eu.kanade.tachiyomi.util.view.shrinkOnScroll
-import eu.kanade.tachiyomi.util.view.visible
 import kotlinx.android.synthetic.main.main_activity.root_coordinator
-import kotlinx.android.synthetic.main.main_activity.root_fab
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import reactivecircus.flowbinding.android.view.clicks
@@ -53,6 +50,7 @@ class CategoryController :
      */
     private var adapter: CategoryAdapter? = null
 
+    private var actionFab: ExtendedFloatingActionButton? = null
     private var actionFabScrollListener: RecyclerView.OnScrollListener? = null
 
     /**
@@ -98,11 +96,11 @@ class CategoryController :
         adapter?.isHandleDragEnabled = true
         adapter?.isPermanentDelete = false
 
-        activity!!.root_fab.visible()
-        actionFabScrollListener = activity!!.root_fab.shrinkOnScroll(binding.recycler)
+        actionFabScrollListener = actionFab?.shrinkOnScroll(binding.recycler)
     }
 
     override fun configureFab(fab: ExtendedFloatingActionButton) {
+        actionFab = fab
         fab.setText(R.string.action_add)
         fab.setIconResource(R.drawable.ic_add_24dp)
         fab.clicks()
@@ -114,6 +112,7 @@ class CategoryController :
 
     override fun cleanupFab(fab: ExtendedFloatingActionButton) {
         actionFabScrollListener?.let { binding.recycler.removeOnScrollListener(it) }
+        actionFab = null
     }
 
     /**
@@ -127,7 +126,6 @@ class CategoryController :
         undoHelper = null
         actionMode = null
         adapter = null
-        activity!!.root_fab.gone()
         super.onDestroyView(view)
     }
 
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/download/DownloadController.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/download/DownloadController.kt
index be0adb310e..15ddd84b7c 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/download/DownloadController.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/download/DownloadController.kt
@@ -20,7 +20,6 @@ import eu.kanade.tachiyomi.util.view.gone
 import eu.kanade.tachiyomi.util.view.shrinkOnScroll
 import eu.kanade.tachiyomi.util.view.visible
 import java.util.concurrent.TimeUnit
-import kotlinx.android.synthetic.main.main_activity.root_fab
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import reactivecircus.flowbinding.android.view.clicks
@@ -42,6 +41,7 @@ class DownloadController :
      */
     private var adapter: DownloadAdapter? = null
 
+    private var actionFab: ExtendedFloatingActionButton? = null
     private var actionFabScrollListener: RecyclerView.OnScrollListener? = null
 
     /**
@@ -87,8 +87,7 @@ class DownloadController :
         binding.recycler.layoutManager = LinearLayoutManager(view.context)
         binding.recycler.setHasFixedSize(true)
 
-        activity!!.root_fab.visible()
-        actionFabScrollListener = activity!!.root_fab.shrinkOnScroll(binding.recycler)
+        actionFabScrollListener = actionFab?.shrinkOnScroll(binding.recycler)
 
         // Subscribe to changes
         DownloadService.runningRelay
@@ -105,6 +104,7 @@ class DownloadController :
     }
 
     override fun configureFab(fab: ExtendedFloatingActionButton) {
+        actionFab = fab
         fab.clicks()
             .onEach {
                 val context = applicationContext ?: return@onEach
@@ -123,6 +123,7 @@ class DownloadController :
 
     override fun cleanupFab(fab: ExtendedFloatingActionButton) {
         actionFabScrollListener?.let { binding.recycler.removeOnScrollListener(it) }
+        actionFab = null
     }
 
     override fun onDestroyView(view: View) {
@@ -130,7 +131,6 @@ class DownloadController :
             subscription.unsubscribe()
         }
         progressSubscriptions.clear()
-        activity!!.root_fab.gone()
         adapter = null
         super.onDestroyView(view)
     }
@@ -284,10 +284,10 @@ class DownloadController :
     private fun setInformationView() {
         if (presenter.downloadQueue.isEmpty()) {
             binding.emptyView.show(R.string.information_no_downloads)
-            activity!!.root_fab.gone()
+            actionFab?.gone()
         } else {
             binding.emptyView.hide()
-            activity!!.root_fab.apply {
+            actionFab?.apply {
                 visible()
 
                 setText(
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/main/MainActivity.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/main/MainActivity.kt
index f11c125944..e9cc2c62e5 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/main/MainActivity.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/main/MainActivity.kt
@@ -43,6 +43,7 @@ import eu.kanade.tachiyomi.ui.recent.updates.UpdatesController
 import eu.kanade.tachiyomi.util.lang.launchIO
 import eu.kanade.tachiyomi.util.lang.launchUI
 import eu.kanade.tachiyomi.util.system.toast
+import eu.kanade.tachiyomi.util.view.gone
 import eu.kanade.tachiyomi.util.view.snack
 import eu.kanade.tachiyomi.util.view.visible
 import java.util.Date
@@ -348,9 +349,11 @@ class MainActivity : BaseActivity<MainActivityBinding>() {
         }
 
         if (from is FabController) {
+            binding.rootFab.gone()
             from.cleanupFab(binding.rootFab)
         }
         if (to is FabController) {
+            binding.rootFab.visible()
             to.configureFab(binding.rootFab)
         }
 
diff --git a/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaController.kt b/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaController.kt
index 122d289839..194775bc0e 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaController.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaController.kt
@@ -68,7 +68,6 @@ import eu.kanade.tachiyomi.util.view.shrinkOnScroll
 import eu.kanade.tachiyomi.util.view.snack
 import eu.kanade.tachiyomi.util.view.visible
 import kotlinx.android.synthetic.main.main_activity.root_coordinator
-import kotlinx.android.synthetic.main.main_activity.root_fab
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import reactivecircus.flowbinding.android.view.clicks
@@ -128,6 +127,7 @@ class MangaController :
      */
     private var settingsSheet: ChaptersSettingsSheet? = null
 
+    private var actionFab: ExtendedFloatingActionButton? = null
     private var actionFabScrollListener: RecyclerView.OnScrollListener? = null
 
     /**
@@ -191,8 +191,7 @@ class MangaController :
         binding.recycler.setHasFixedSize(true)
         chaptersAdapter?.fastScroller = binding.fastScroller
 
-        activity!!.root_fab.visible()
-        actionFabScrollListener = activity!!.root_fab.shrinkOnScroll(binding.recycler)
+        actionFabScrollListener = actionFab?.shrinkOnScroll(binding.recycler)
 
         // Skips directly to chapters list if navigated to from the library
         binding.recycler.post {
@@ -225,6 +224,7 @@ class MangaController :
     }
 
     override fun configureFab(fab: ExtendedFloatingActionButton) {
+        actionFab = fab
         fab.setText(R.string.action_start)
         fab.setIconResource(R.drawable.ic_play_arrow_24dp)
         fab.clicks()
@@ -239,14 +239,15 @@ class MangaController :
                     }
 
                     // Get coordinates and start animation
-                    val coordinates = fab.getCoordinates()
-                    if (!binding.revealView.showRevealEffect(
-                        coordinates.x,
-                        coordinates.y,
-                        revealAnimationListener
-                    )
-                    ) {
-                        openChapter(item.chapter)
+                    actionFab?.getCoordinates()?.let { coordinates ->
+                        if (!binding.revealView.showRevealEffect(
+                            coordinates.x,
+                            coordinates.y,
+                            revealAnimationListener
+                        )
+                        ) {
+                            openChapter(item.chapter)
+                        }
                     }
                 } else {
                     view?.context?.toast(R.string.no_next_chapter)
@@ -257,12 +258,12 @@ class MangaController :
 
     override fun cleanupFab(fab: ExtendedFloatingActionButton) {
         actionFabScrollListener?.let { binding.recycler.removeOnScrollListener(it) }
+        actionFab = null
     }
 
     override fun onDestroyView(view: View) {
         destroyActionModeIfNeeded()
         binding.actionToolbar.destroy()
-        activity!!.root_fab.gone()
         mangaInfoAdapter = null
         chaptersHeaderAdapter = null
         chaptersAdapter = null
@@ -276,8 +277,9 @@ class MangaController :
         // Check if animation view is visible
         if (binding.revealView.visibility == View.VISIBLE) {
             // Show the unreveal effect
-            val coordinates = activity.root_fab.getCoordinates()
-            binding.revealView.hideRevealEffect(coordinates.x, coordinates.y, 1920)
+            actionFab?.getCoordinates()?.let { coordinates ->
+                binding.revealView.hideRevealEffect(coordinates.x, coordinates.y, 1920)
+            }
         }
 
         super.onActivityResumed(activity)
@@ -619,7 +621,7 @@ class MangaController :
 
         val context = view?.context
         if (context != null && chapters.any { it.read }) {
-            activity!!.root_fab.text = context.getString(R.string.action_resume)
+            actionFab?.text = context.getString(R.string.action_resume)
         }
     }
 
@@ -759,8 +761,8 @@ class MangaController :
             binding.actionToolbar.findItem(R.id.action_mark_as_unread)?.isVisible = chapters.all { it.chapter.read }
 
             // Hide FAB to avoid interfering with the bottom action toolbar
-            // activity!!.root_fab.hide()
-            activity!!.root_fab.gone()
+            // actionFab?.hide()
+            actionFab?.gone()
         }
         return false
     }
@@ -794,8 +796,8 @@ class MangaController :
 
         // TODO: there seems to be a bug in MaterialComponents where the [ExtendedFloatingActionButton]
         // fails to show up properly
-        // activity!!.root_fab.show()
-        activity!!.root_fab.visible()
+        // actionFab?.show()
+        actionFab?.visible()
     }
 
     override fun onDetach(view: View) {