diff --git a/build.gradle b/build.gradle
index 27ece090..8bd32338 100644
--- a/build.gradle
+++ b/build.gradle
@@ -109,16 +109,16 @@ dependencies {
         because "de-/serialization of launcher properties to JSON"
     }
 
-    implementation('com.squareup.okhttp3:okhttp:4.10.0') {
+    implementation('com.squareup.okhttp3:okhttp:4.12.0') {
         because "built-in caching of HTTP requests"
     }
 
     // These dependencies are only needed for running tests
 
     testImplementation 'org.hamcrest:hamcrest:2.2'
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.9.2'
-    testImplementation 'org.junit.jupiter:junit-jupiter-params:5.9.2'
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.9.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.10.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-params:5.10.2'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.10.2'
 
     testImplementation('org.mockito:mockito-inline:5.2.0') {
         because "-inline build enables mocking final classes"
@@ -134,18 +134,18 @@ dependencies {
         because "spf4j-slf4j-test:8.8 needs slf4j-api:1.x"
     }
 
-    testImplementation("org.testfx:testfx-core:4.0.16-alpha") {
+    testImplementation("org.testfx:testfx-core:4.0.18") {
         because "to test JavaFX Application"
         // -alpha because that's the only kind of release they have?
     }
-    testImplementation "org.testfx:testfx-junit5:4.0.16-alpha"
+    testImplementation "org.testfx:testfx-junit5:4.0.18"
 
-    testImplementation("org.testfx:openjfx-monocle:jdk-12.0.1+2") {
+    testImplementation("org.testfx:openjfx-monocle:17.0.10") {
         // nobody's uploaded a jdk-14 build yet. does the jdk-12 one work?
         because "CI builders are headless environments"
     }
 
-    testImplementation('com.github.gmazzo:okhttp-mock:1.5.0') {
+    testImplementation('com.github.gmazzo.okhttp.mock:mock-client:2.0.0') {
         because "to easily write OkHttpClient interceptors for testing"
     }
     testImplementation('com.squareup.okhttp3:mockwebserver:4.10.0') {
diff --git a/gradle.lockfile b/gradle.lockfile
index 75d7207e..67c8ae85 100644
--- a/gradle.lockfile
+++ b/gradle.lockfile
@@ -22,9 +22,9 @@ com.openhtmltopdf:openhtmltopdf-core:1.0.10=compileClasspath
 com.openhtmltopdf:openhtmltopdf-jsoup-dom-converter:1.0.0=compileClasspath
 com.openhtmltopdf:openhtmltopdf-pdfbox:1.0.10=compileClasspath
 com.openhtmltopdf:openhtmltopdf-rtl-support:1.0.10=compileClasspath
-com.squareup.okhttp3:okhttp:4.10.0=compileClasspath
-com.squareup.okio:okio-jvm:3.0.0=compileClasspath
-com.squareup.okio:okio:3.0.0=compileClasspath
+com.squareup.okhttp3:okhttp:4.12.0=compileClasspath
+com.squareup.okio:okio-jvm:3.6.0=compileClasspath
+com.squareup.okio:okio:3.6.0=compileClasspath
 com.vladsch.flexmark:flexmark-all:0.64.0=compileClasspath
 com.vladsch.flexmark:flexmark-ext-abbreviation:0.64.0=compileClasspath
 com.vladsch.flexmark:flexmark-ext-admonition:0.64.0=compileClasspath
@@ -87,10 +87,10 @@ org.apache.pdfbox:pdfbox:2.0.24=compileClasspath
 org.apache.pdfbox:xmpbox:2.0.24=compileClasspath
 org.checkerframework:checker-qual:3.12.0=compileClasspath
 org.hildan.fxgson:fx-gson:5.0.0=compileClasspath
-org.jetbrains.kotlin:kotlin-stdlib-common:1.6.20=compileClasspath
-org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.6.20=compileClasspath
-org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.6.20=compileClasspath
-org.jetbrains.kotlin:kotlin-stdlib:1.6.20=compileClasspath
+org.jetbrains.kotlin:kotlin-stdlib-common:1.9.10=compileClasspath
+org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.9.10=compileClasspath
+org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.9.10=compileClasspath
+org.jetbrains.kotlin:kotlin-stdlib:1.9.10=compileClasspath
 org.jetbrains:annotations:23.0.0=compileClasspath
 org.json:json:20220320=compileClasspath
 org.jsoup:jsoup:1.14.3=compileClasspath