diff --git a/.github/actions/setup/action.yml b/.github/actions/setup/action.yml
index deff7f3efea..f3446bfc3dd 100644
--- a/.github/actions/setup/action.yml
+++ b/.github/actions/setup/action.yml
@@ -11,7 +11,7 @@ runs:
       uses: actions/setup-java@c5195efecf7bdfc987ee8bae7a71cb8b11521c00 # v4.7.1
       with:
         distribution: 'temurin'
-        java-version: '17'
+        java-version: '21'
 
     - name: Set up Gradle
       uses: gradle/actions/setup-gradle@ac638b010cf58a27ee6c972d7336334ccaf61c96 # v4.4.1
diff --git a/.github/workflows/android.yml b/.github/workflows/android.yml
index 9d146685ad2..734f1898f8a 100644
--- a/.github/workflows/android.yml
+++ b/.github/workflows/android.yml
@@ -32,7 +32,7 @@ jobs:
       - uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5.0.0
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@748248ddd2a24f49513d8f472f81c3a07d4d50e1 # v4.4.4
diff --git a/.github/workflows/markdown.yml b/.github/workflows/markdown.yml
index 4613be078d7..1c0acd30279 100644
--- a/.github/workflows/markdown.yml
+++ b/.github/workflows/markdown.yml
@@ -28,7 +28,7 @@ jobs:
       - uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5.0.0
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@748248ddd2a24f49513d8f472f81c3a07d4d50e1 # v4.4.4
diff --git a/.github/workflows/shippable_builds.yml b/.github/workflows/shippable_builds.yml
index b291d3eb21c..8a40f3c36a8 100644
--- a/.github/workflows/shippable_builds.yml
+++ b/.github/workflows/shippable_builds.yml
@@ -229,7 +229,7 @@ jobs:
         if: ${{ contains(matrix.releaseTarget, 'github') || needs.dump_config.outputs.releaseType == 'daily' }}
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@748248ddd2a24f49513d8f472f81c3a07d4d50e1 # v4.4.4
@@ -477,7 +477,7 @@ jobs:
       - uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5.0.0
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@748248ddd2a24f49513d8f472f81c3a07d4d50e1 # v4.4.4
diff --git a/docs/contributing/development-environment.md b/docs/contributing/development-environment.md
index 456181ea490..3c21bf98564 100644
--- a/docs/contributing/development-environment.md
+++ b/docs/contributing/development-environment.md
@@ -7,7 +7,7 @@ Android project.
 
 Before you begin, ensure you have the following installed:
 
-- **[Java Development Kit (JDK)](https://adoptium.net/temurin/releases/?version=17)** - Version 17 or higher (Temurin OpenJDK recommended)
+- **[Java Development Kit (JDK)](https://adoptium.net/temurin/releases/?version=21)** - Version 21 or higher (Temurin OpenJDK recommended)
 - **[Android Studio](https://developer.android.com/studio)** - Latest stable version recommended
 - **[Git](https://git-scm.com/downloads)** - For version control
 - **Gradle** - Use the Gradle wrapper included in this repo (`./gradlew`); no separate install required
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 0f24c2849c4..35e729b0cc0 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -102,7 +102,7 @@ mozillaAndroidComponents = "143.0.2"
 okhttp = "5.1.0"
 okio = "3.16.0"
 preferencesFix = "1.1.0"
-robolectric = "4.15.1"
+robolectric = "4.16"
 safeContentResolver = "1.0.0"
 searchPreference = "2.7.3"
 spotlessPlugin = "8.0.0"
diff --git a/settings.gradle.kts b/settings.gradle.kts
index 35fb8a7bd7c..0e3a5216475 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -251,14 +251,14 @@ include(
     ":feature:debug-settings",
 )
 
-check(JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_17)) {
+check(JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_21)) {
     """
-        Java 17+ is required to build Thunderbird for Android.
+        Java 21+ is required to build Thunderbird for Android.
         But it found an incompatible Java version ${{ JavaVersion.current() }}.
 
         Java Home: [${System.getProperty("java.home")}]
 
-        Please install Java 17+ and set JAVA_HOME to the directory containing the Java 17+ installation.
+        Please install Java 21+ and set JAVA_HOME to the directory containing the Java 21+ installation.
         https://developer.android.com/build/jdks#jdk-config-in-studio
     """.trimIndent()
 }