diff --git a/webauthn-server-attestation/build.gradle.kts b/webauthn-server-attestation/build.gradle.kts
index 94f5a34a4..80e8de8bd 100644
--- a/webauthn-server-attestation/build.gradle.kts
+++ b/webauthn-server-attestation/build.gradle.kts
@@ -45,13 +45,7 @@ dependencies {
   testImplementation("org.scalatest:scalatest_2.13")
   testImplementation("org.scalatestplus:junit-4-13_2.13")
   testImplementation("org.scalatestplus:scalacheck-1-16_2.13")
-
-  testImplementation("org.slf4j:slf4j-api") {
-    version {
-      strictly("[1.7.25,1.8-a)") // Pre-1.8 version required by slf4j-test
-    }
-  }
-  testRuntimeOnly("uk.org.lidalia:slf4j-test")
+  testImplementation("org.slf4j:slf4j-api")
 }
 
 val integrationTest = task<Test>("integrationTest") {
diff --git a/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyAssertionSpec.scala b/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyAssertionSpec.scala
index 29d7c7396..995308afc 100644
--- a/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyAssertionSpec.scala
+++ b/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyAssertionSpec.scala
@@ -1168,7 +1168,7 @@ class RelyingPartyAssertionSpec
                   genCredentialIdAndAllowCredentials,
                   genUsernameOrUserHandle,
                   genUserHandle,
-                  maxDiscardedFactor(20), // This helps the `whenever` clause below not make the test flaky
+                  maxDiscardedFactor(30), // This helps the `whenever` clause below not make the test flaky
                 ) {
                   case (
                         (credentialId, allowCredentials),
diff --git a/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyV2AssertionSpec.scala b/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyV2AssertionSpec.scala
index 5c056b0cc..0b9d5df91 100644
--- a/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyV2AssertionSpec.scala
+++ b/webauthn-server-core/src/test/scala/com/yubico/webauthn/RelyingPartyV2AssertionSpec.scala
@@ -1159,7 +1159,7 @@ class RelyingPartyV2AssertionSpec
                     genCredentialIdAndAllowCredentials,
                     genUserIdentifiers,
                     genUserHandle,
-                    maxDiscardedFactor(20), // This helps the `whenever` clause below not make the test flaky
+                    maxDiscardedFactor(30), // This helps the `whenever` clause below not make the test flaky
                   ) {
                     case (
                           (credentialId, allowCredentials),