diff --git a/CHANGELOG.md b/CHANGELOG.md
index c22e1d0..190208d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,7 +5,7 @@
 - Configure Gradle build to explicitly specify JDK 21 requirements for better IDE integration
 - update dependencies
 - upgrade to gradle 9.x
-- upgrade to intellij 2025.3
+- upgrade to intellij 2026.2
 
 ## [1.11.0]
 
diff --git a/build.gradle b/build.gradle
index 03c19f7..1f4bc3e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,8 +1,8 @@
 import org.jetbrains.changelog.Changelog
 
 plugins {
-    id 'org.jetbrains.kotlin.jvm' version "2.3.21"
-    id 'org.jetbrains.intellij.platform' version '2.14.0'
+    id 'org.jetbrains.kotlin.jvm' version "2.4.10"
+    id 'org.jetbrains.intellij.platform' version '2.18.1'
     id 'org.jetbrains.changelog' version '2.5.0'
 }
 
@@ -28,19 +28,22 @@ dependencies {
     implementation 'com.squareup:gifencoder:0.10.1'
 
     intellijPlatform {
-        intellijIdea('2025.3')
+        intellijIdea('2026.2')
     }
 
-    testImplementation('org.junit.jupiter:junit-jupiter:5.7.2')
-    testImplementation('org.mockito.kotlin:mockito-kotlin:5.4.0')
-    testImplementation('junit:junit:4.13.2')
-    testImplementation('org.jetbrains.kotlin:kotlin-test:2.3.21')
+    testImplementation('org.junit.jupiter:junit-jupiter:6.1.2')
+    testImplementation('org.mockito.kotlin:mockito-kotlin:6.3.0')
+    testImplementation('org.jetbrains.kotlin:kotlin-test:2.4.10')
+}
+
+test {
+    useJUnitPlatform()
 }
 
 intellijPlatform {
     pluginConfiguration {
         ideaVersion {
-            sinceBuild.set('253')
+            sinceBuild.set('262')
         }
         changeNotes.set(provider({changelog.renderItem(changelog.getLatest(), Changelog.OutputType.HTML)}))
     }
diff --git a/src/main/resources/META-INF/plugin.xml b/src/main/resources/META-INF/plugin.xml
index 35813e0..665b085 100644
--- a/src/main/resources/META-INF/plugin.xml
+++ b/src/main/resources/META-INF/plugin.xml
@@ -8,7 +8,7 @@
      I am happy if you report issues, I am going to fix them.
     ]]></description>
 
-    <idea-version since-build="253"/>
+    <idea-version since-build="262"/>
 
     <depends>com.intellij.modules.lang</depends>
 
diff --git a/src/test/kotlin/de/ehmkah/projects/imgdiff/DiffedImageCreatorTest.kt b/src/test/kotlin/de/ehmkah/projects/imgdiff/DiffedImageCreatorTest.kt
index ac70ae1..a4ce6ab 100644
--- a/src/test/kotlin/de/ehmkah/projects/imgdiff/DiffedImageCreatorTest.kt
+++ b/src/test/kotlin/de/ehmkah/projects/imgdiff/DiffedImageCreatorTest.kt
@@ -1,7 +1,7 @@
 package de.ehmkah.projects.imgdiff
 
-import org.junit.Assert.assertTrue
-import org.junit.Test
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
 import java.awt.image.BufferedImage
 import java.io.ByteArrayOutputStream
 import java.io.File
diff --git a/src/test/kotlin/de/ehmkah/projects/imgdiff/ImgDiffBaseBinaryDiffToolTest.kt b/src/test/kotlin/de/ehmkah/projects/imgdiff/ImgDiffBaseBinaryDiffToolTest.kt
index 3da7bea..dc8d772 100644
--- a/src/test/kotlin/de/ehmkah/projects/imgdiff/ImgDiffBaseBinaryDiffToolTest.kt
+++ b/src/test/kotlin/de/ehmkah/projects/imgdiff/ImgDiffBaseBinaryDiffToolTest.kt
@@ -6,7 +6,7 @@ import com.intellij.openapi.fileTypes.FileType
 import com.intellij.openapi.vfs.VirtualFile
 import org.mockito.kotlin.doReturn
 import org.mockito.kotlin.mock
-import org.junit.Test
+import org.junit.jupiter.api.Test
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue