diff --git a/app/src/main/java/org/tasks/preferences/MainPreferences.kt b/app/src/main/java/org/tasks/preferences/MainPreferences.kt
index f168054ca..b24a44561 100644
--- a/app/src/main/java/org/tasks/preferences/MainPreferences.kt
+++ b/app/src/main/java/org/tasks/preferences/MainPreferences.kt
@@ -2,10 +2,8 @@ package org.tasks.preferences
 
 import android.app.Activity
 import android.content.Intent
-import androidx.lifecycle.lifecycleScope
 import com.todoroo.astrid.gtasks.auth.GtasksLoginActivity
 import dagger.hilt.android.AndroidEntryPoint
-import kotlinx.coroutines.launch
 import org.tasks.R
 import org.tasks.drive.DriveLoginActivity
 import org.tasks.jobs.WorkManager
@@ -32,16 +30,12 @@ class MainPreferences : BasePreferences() {
         if (requestCode == REQUEST_CALDAV_SETTINGS) {
             if (resultCode == RESULT_OK) {
                 syncAdapters.sync(true)
-                lifecycleScope.launch {
-                    workManager.updateBackgroundSync()
-                }
+                workManager.updateBackgroundSync()
             }
         } else if (requestCode == REQUEST_GOOGLE_TASKS) {
             if (resultCode == Activity.RESULT_OK) {
                 syncAdapters.sync(true)
-                lifecycleScope.launch {
-                    workManager.updateBackgroundSync()
-                }
+                workManager.updateBackgroundSync()
             } else {
                 data?.getStringExtra(GtasksLoginActivity.EXTRA_ERROR)?.let { toaster.longToast(it) }
             }
diff --git a/app/src/main/java/org/tasks/preferences/fragments/Synchronization.kt b/app/src/main/java/org/tasks/preferences/fragments/Synchronization.kt
index 2c838a440..ff9afc14b 100644
--- a/app/src/main/java/org/tasks/preferences/fragments/Synchronization.kt
+++ b/app/src/main/java/org/tasks/preferences/fragments/Synchronization.kt
@@ -1,6 +1,5 @@
 package org.tasks.preferences.fragments
 
-import android.app.Activity
 import android.content.Intent
 import android.os.Bundle
 import androidx.lifecycle.lifecycleScope
@@ -33,6 +32,7 @@ import javax.inject.Inject
 
 const val REQUEST_CALDAV_SETTINGS = 10013
 const val REQUEST_GOOGLE_TASKS = 10014
+private const val FRAG_TAG_ADD_ACCOUNT = "frag_tag_add_account"
 
 @AndroidEntryPoint
 class Synchronization : InjectingPreferenceFragment() {
@@ -80,7 +80,7 @@ class Synchronization : InjectingPreferenceFragment() {
 
         findPreference(R.string.add_account)
             .setOnPreferenceClickListener {
-                AddAccountDialog.showAddAccountDialog(requireActivity(), dialogBuilder)
+                AddAccountDialog().show(parentFragmentManager, FRAG_TAG_ADD_ACCOUNT)
                 false
             }
     }
@@ -91,19 +91,6 @@ class Synchronization : InjectingPreferenceFragment() {
         refresh()
     }
 
-    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
-        if (requestCode == REQUEST_CALDAV_SETTINGS) {
-            if (resultCode == Activity.RESULT_OK) {
-                syncAdapters.sync(true)
-                lifecycleScope.launch {
-                    workManager.updateBackgroundSync()
-                }
-            }
-        } else {
-            super.onActivityResult(requestCode, resultCode, data)
-        }
-    }
-
     private suspend fun addGoogleTasksAccounts(category: PreferenceCategory): Boolean {
         val accounts: List<GoogleTaskAccount> = googleTaskListDao.getAccounts()
         for (googleTaskAccount in accounts) {
diff --git a/app/src/main/java/org/tasks/sync/AddAccountDialog.kt b/app/src/main/java/org/tasks/sync/AddAccountDialog.kt
index f83066a49..137b16bd6 100644
--- a/app/src/main/java/org/tasks/sync/AddAccountDialog.kt
+++ b/app/src/main/java/org/tasks/sync/AddAccountDialog.kt
@@ -1,15 +1,17 @@
 package org.tasks.sync
 
-import android.app.Activity
-import android.content.DialogInterface
+import android.app.Dialog
 import android.content.Intent
 import android.net.Uri
+import android.os.Bundle
 import android.view.View
 import android.view.ViewGroup
 import android.widget.ArrayAdapter
 import android.widget.ImageView
 import android.widget.TextView
+import androidx.fragment.app.DialogFragment
 import com.todoroo.astrid.gtasks.auth.GtasksLoginActivity
+import dagger.hilt.android.AndroidEntryPoint
 import org.tasks.R
 import org.tasks.caldav.CaldavAccountSettingsActivity
 import org.tasks.dialogs.DialogBuilder
@@ -17,19 +19,24 @@ import org.tasks.etesync.EteSyncAccountSettingsActivity
 import org.tasks.preferences.fragments.REQUEST_CALDAV_SETTINGS
 import org.tasks.preferences.fragments.REQUEST_GOOGLE_TASKS
 import org.tasks.themes.DrawableUtil
+import javax.inject.Inject
 
-object AddAccountDialog {
-    fun showAddAccountDialog(activity: Activity, dialogBuilder: DialogBuilder) {
-        val services = activity.resources.getStringArray(R.array.synchronization_services)
-        val descriptions = activity.resources.getStringArray(R.array.synchronization_services_description)
-        val typedArray = activity.resources.obtainTypedArray(R.array.synchronization_services_icons)
+@AndroidEntryPoint
+class AddAccountDialog : DialogFragment() {
+
+    @Inject lateinit var dialogBuilder: DialogBuilder
+
+    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
+        val services = requireActivity().resources.getStringArray(R.array.synchronization_services)
+        val descriptions = requireActivity().resources.getStringArray(R.array.synchronization_services_description)
+        val typedArray = requireActivity().resources.obtainTypedArray(R.array.synchronization_services_icons)
         val icons = IntArray(typedArray.length())
         for (i in icons.indices) {
             icons[i] = typedArray.getResourceId(i, 0)
         }
         typedArray.recycle()
         val adapter: ArrayAdapter<String> = object : ArrayAdapter<String>(
-                activity, R.layout.simple_list_item_2_themed, R.id.text1, services) {
+                requireActivity(), R.layout.simple_list_item_2_themed, R.id.text1, services) {
             override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {
                 val view = super.getView(position, convertView, parent)
                 view.findViewById<TextView>(R.id.text1).text = services[position]
@@ -42,32 +49,30 @@ object AddAccountDialog {
                 return view
             }
         }
-        dialogBuilder
+        return dialogBuilder
                 .newDialog()
                 .setTitle(R.string.choose_synchronization_service)
-                .setSingleChoiceItems(
-                        adapter,
-                        -1
-                ) { dialog: DialogInterface, which: Int ->
+                .setSingleChoiceItems(adapter, -1) { dialog, which ->
                     when (which) {
-                        0 -> activity.startActivityForResult(
+                        0 -> activity?.startActivityForResult(
                                 Intent(activity, GtasksLoginActivity::class.java),
                                 REQUEST_GOOGLE_TASKS)
-                        1 -> activity.startActivityForResult(
+                        1 -> activity?.startActivityForResult(
                                 Intent(activity, CaldavAccountSettingsActivity::class.java),
                                 REQUEST_CALDAV_SETTINGS)
-                        2 -> activity.startActivityForResult(
+                        2 -> activity?.startActivityForResult(
                                 Intent(activity, EteSyncAccountSettingsActivity::class.java),
                                 REQUEST_CALDAV_SETTINGS)
                     }
                     dialog.dismiss()
                 }
                 .setNeutralButton(R.string.help) { _, _ ->
-                    activity.startActivity(
-                            Intent(
-                                    Intent.ACTION_VIEW, Uri.parse(activity.getString(R.string.help_url_sync))))
+                    activity?.startActivity(Intent(
+                            Intent.ACTION_VIEW,
+                            Uri.parse(context?.getString(R.string.help_url_sync))))
                 }
                 .setNegativeButton(android.R.string.cancel, null)
                 .show()
     }
+
 }
\ No newline at end of file