diff --git a/.travis.yml b/.travis.yml
index 0b8a5ad9de4c29b694337dab59e618a9810f1171..2c30c673bcbea7a8ef1ce2e5965adeb2280d527b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 ---
 os: linux
-dist: xenial
+dist: focal
 language: generic
 env:
   - PDK=release PDK_FRONTEND=noninteractive
diff --git a/config_defaults.yml b/config_defaults.yml
index 63cce235ef0d33b6d4221fcbeaa7de43a7026617..30c080dd0c1d50b3c15bb845809ffbe0eda4d0cb 100644
--- a/config_defaults.yml
+++ b/config_defaults.yml
@@ -557,7 +557,9 @@ Gemfile:
   required:
     ':development':
       - gem: 'json'
-        version: '~> 2.0'
+        version:
+        - '~> 2.0'
+        - '!= 2.6.2'
       - gem: 'voxpupuli-puppet-lint-plugins'
         version: '~> 3.0'
       - gem: 'facterdb'