diff --git a/app/build.gradle b/app/build.gradle
index 28929ca405..1fa77edb17 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -22,7 +22,7 @@ final def CUSTOM_INSTANCE = ""
 final def SUPPORT_ACCOUNT_URL = "https://mastodon.social/@Tusky"
 
 android {
-    compileSdk 33
+    compileSdk 34
     namespace "com.keylesspalace.tusky"
     defaultConfig {
         applicationId APP_ID
diff --git a/app/src/main/java/com/keylesspalace/tusky/components/preference/PreferencesActivity.kt b/app/src/main/java/com/keylesspalace/tusky/components/preference/PreferencesActivity.kt
index 9b79f3ce7b..91d87e9f98 100644
--- a/app/src/main/java/com/keylesspalace/tusky/components/preference/PreferencesActivity.kt
+++ b/app/src/main/java/com/keylesspalace/tusky/components/preference/PreferencesActivity.kt
@@ -144,7 +144,9 @@ class PreferencesActivity :
         super.onSaveInstanceState(outState)
     }
 
-    override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences, key: String) {
+    override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences?, key: String?) {
+        sharedPreferences ?: return
+        key ?: return
         when (key) {
             APP_THEME -> {
                 val theme = sharedPreferences.getNonNullString(APP_THEME, AppTheme.DEFAULT.value)
diff --git a/app/src/main/java/com/keylesspalace/tusky/fragment/ViewVideoFragment.kt b/app/src/main/java/com/keylesspalace/tusky/fragment/ViewVideoFragment.kt
index 6cd13c076c..688f0217dc 100644
--- a/app/src/main/java/com/keylesspalace/tusky/fragment/ViewVideoFragment.kt
+++ b/app/src/main/java/com/keylesspalace/tusky/fragment/ViewVideoFragment.kt
@@ -155,7 +155,7 @@ class ViewVideoFragment : ViewMediaFragment(), Injectable {
 
                     /** A fling up/down should dismiss the fragment */
                     override fun onFling(
-                        e1: MotionEvent,
+                        e1: MotionEvent?,
                         e2: MotionEvent,
                         velocityX: Float,
                         velocityY: Float
diff --git a/app/src/main/java/com/keylesspalace/tusky/view/ClickableSpanTextView.kt b/app/src/main/java/com/keylesspalace/tusky/view/ClickableSpanTextView.kt
index 4caf47c149..0c60a04c44 100644
--- a/app/src/main/java/com/keylesspalace/tusky/view/ClickableSpanTextView.kt
+++ b/app/src/main/java/com/keylesspalace/tusky/view/ClickableSpanTextView.kt
@@ -347,21 +347,21 @@ class ClickableSpanTextView @JvmOverloads constructor(
         return firstDiff < secondDiff
     }
 
-    override fun onDraw(canvas: Canvas?) {
+    override fun onDraw(canvas: Canvas) {
         super.onDraw(canvas)
 
         // Paint span boundaries. Optimised out on release builds, or debug builds where
         // showSpanBoundaries is false.
         if (BuildConfig.DEBUG && showSpanBoundaries) {
-            canvas?.save()
+            canvas.save()
             for (entry in delegateRects) {
-                canvas?.drawRect(entry.key, paddingDebugPaint)
+                canvas.drawRect(entry.key, paddingDebugPaint)
             }
 
             for (entry in spanRects) {
-                canvas?.drawRect(entry.key, spanDebugPaint)
+                canvas.drawRect(entry.key, spanDebugPaint)
             }
-            canvas?.restore()
+            canvas.restore()
         }
     }
 
diff --git a/app/src/main/java/com/keylesspalace/tusky/view/GraphView.kt b/app/src/main/java/com/keylesspalace/tusky/view/GraphView.kt
index 2aecad08d6..e6a54a2bce 100644
--- a/app/src/main/java/com/keylesspalace/tusky/view/GraphView.kt
+++ b/app/src/main/java/com/keylesspalace/tusky/view/GraphView.kt
@@ -265,14 +265,14 @@ class GraphView @JvmOverloads constructor(
 
     private fun dataSpacing(data: List<Any>) = width.toFloat() / max(data.size - 1, 1).toFloat()
 
-    override fun onDraw(canvas: Canvas?) {
+    override fun onDraw(canvas: Canvas) {
         super.onDraw(canvas)
 
         if (primaryLinePath.isEmpty && width > 0) {
             initializeVertices()
         }
 
-        canvas?.apply {
+        canvas.apply {
             drawRect(sizeRect, graphPaint)
 
             val pointDistance = dataSpacing(primaryLineData)