diff --git a/.github/workflows/unit-tests.yml b/.github/workflows/unit-tests.yml
index 9036833a51e..dc293bb238c 100644
--- a/.github/workflows/unit-tests.yml
+++ b/.github/workflows/unit-tests.yml
@@ -36,27 +36,44 @@ jobs:
             -   name: Setup Gradle
                 uses: gradle/actions/setup-gradle@8da46b539cd8fe6ab27ca75128919a18d757604c # v6.4.1
 
-            -   name: Read the Robolectric version
+            # The cache holds one jar per SDK level the tests run on (@Config(sdk = [..])). Its key names the levels, so
+            # a test on a new level gets a new cache instead of downloading that jar on every run.
+            -   name: Read the Robolectric version and SDK levels
                 id: robolectric
-                run: echo "version=$(grep -oP 'org\.robolectric:robolectric:\K[0-9.]+' app/build.gradle.kts)" >> "$GITHUB_OUTPUT"
+                run: |
+                    {
+                        echo "version=$(grep -oP 'org\.robolectric:robolectric:\K[0-9.]+' app/build.gradle.kts)"
+                        echo "sdks=$(grep -rhoP 'sdk\s*=\s*\[\K[0-9, ]+' app/src/test | tr -d ' ' | tr ',' '\n' | sort -un | paste -sd- -)"
+                    } >> "$GITHUB_OUTPUT"
 
             -   name: Restore the Robolectric Android SDK jars
                 id: robolectric-cache
                 uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
                 with:
                     path: ~/.m2/repository/org/robolectric
-                    key: robolectric-sdks-${{ runner.os }}-${{ steps.robolectric.outputs.version }}
+                    key: robolectric-sdks-${{ runner.os }}-${{ steps.robolectric.outputs.version }}-${{ steps.robolectric.outputs.sdks }}
 
             -   name: Run unit tests with coverage
                 run: ./gradlew --no-daemon testGplayDebugUnit
 
+            # A cache is never replaced once its key exists, so only one with a jar for every SDK level is saved.
+            -   name: Check the Robolectric Android SDK jars
+                id: robolectric-jars
+                if: ${{ always() && steps.robolectric-cache.outputs.cache-hit != 'true' }}
+                env:
+                    SDKS: ${{ steps.robolectric.outputs.sdks }}
+                run: |
+                    jars=$(find ~/.m2/repository/org/robolectric/android-all-instrumented -name '*.jar' 2>/dev/null | wc -l)
+                    levels=$(echo "$SDKS" | tr '-' '\n' | wc -l)
+                    echo "complete=$([ "$jars" -ge "$levels" ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
+
             # Saved even when the suite fails, so a red run still leaves the jars behind.
             -   name: Save the Robolectric Android SDK jars
-                if: ${{ always() && steps.robolectric-cache.outputs.cache-hit != 'true' }}
+                if: ${{ always() && steps.robolectric-jars.outputs.complete == 'true' }}
                 uses: actions/cache/save@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
                 with:
                     path: ~/.m2/repository/org/robolectric
-                    key: robolectric-sdks-${{ runner.os }}-${{ steps.robolectric.outputs.version }}
+                    key: robolectric-sdks-${{ runner.os }}-${{ steps.robolectric.outputs.version }}-${{ steps.robolectric.outputs.sdks }}
 
             -   name: Upload test artifacts
                 if: ${{ failure() }}
diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 2d16654afaf..da64a8770b7 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -108,6 +108,12 @@ android {
             // Gradle's 512m default is too small for the Robolectric suites
             it.maxHeapSize = "2g"
             it.testLogging.events("started", "failed", "skipped")
+            // Robolectric downloads its Android SDK jars itself, from Maven Central unless told otherwise. Take
+            // them from the mirror the build uses too, see build.gradle; Robolectric checks their SHA-512.
+            it.systemProperty(
+                "robolectric.dependency.repo.url",
+                "https://maven-central.storage-download.googleapis.com/maven2/"
+            )
         }
         unitTests.isReturnDefaultValues = true
     }
diff --git a/build.gradle b/build.gradle
index 4f2927f46fe..41083640dfb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -17,6 +17,9 @@ buildscript {
     repositories {
         google()
         gradlePluginPortal()
+        // Google's mirror of Maven Central, first: Maven Central rate-limits the CI runners (HTTP 429). The dependency
+        // verification in gradle/verification-metadata.xml checks each artifact, whichever repository serves it.
+        maven { url = 'https://maven-central.storage-download.googleapis.com/maven2/' }
         mavenCentral()
     }
 
@@ -42,6 +45,9 @@ configurations.configureEach {
 allprojects {
     repositories {
         google()
+        // Google's mirror of Maven Central, first: Maven Central rate-limits the CI runners (HTTP 429). The dependency
+        // verification in gradle/verification-metadata.xml checks each artifact, whichever repository serves it.
+        maven { url = 'https://maven-central.storage-download.googleapis.com/maven2/' }
         mavenCentral()
         maven {
             url = 'https://jitpack.io'
diff --git a/scripts/analysis/lint-results.txt b/scripts/analysis/lint-results.txt
index b1a91c63f74..8f8c5f61165 100644
--- a/scripts/analysis/lint-results.txt
+++ b/scripts/analysis/lint-results.txt
@@ -1,2 +1,2 @@
 DO NOT TOUCH; GENERATED BY DRONE
-      <span class="mdl-layout-title">Lint Report: 14 warnings</span>
+      <span class="mdl-layout-title">Lint Report: 17 warnings</span>