Specify a stable Jekyll version to use

Gemfile.lock

@@ -1,37 +1,37 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.8.0)
-      public_suffix (>= 2.0.2, < 5.0)
+    addressable (2.8.1)
+      public_suffix (>= 2.0.2, < 6.0)
     colorator (1.1.0)
-    concurrent-ruby (1.1.6)
+    concurrent-ruby (1.1.10)
     cssminify2 (2.0.1)
-    em-websocket (0.5.1)
+    em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
-      http_parser.rb (~> 0.6.0)
+      http_parser.rb (~> 0)
     eventmachine (1.2.7)
-    execjs (2.7.0)
-    ffi (1.13.1)
+    execjs (2.8.1)
+    ffi (1.15.5)
     forwardable-extended (2.6.0)
     htmlcompressor (0.4.0)
-    http_parser.rb (0.6.0)
-    i18n (1.8.5)
+    http_parser.rb (0.8.0)
+    i18n (1.12.0)
       concurrent-ruby (~> 1.0)
-    jekyll (4.1.1)
+    jekyll (4.2.2)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
       i18n (~> 1.0)
       jekyll-sass-converter (~> 2.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 2.1)
+      kramdown (~> 2.3)
       kramdown-parser-gfm (~> 1.0)
       liquid (~> 4.0)
       mercenary (~> 0.4.0)
       pathutil (~> 0.9)
       rouge (~> 3.0)
       safe_yaml (~> 1.0)
-      terminal-table (~> 1.8)
+      terminal-table (~> 2.0)
     jekyll-minifier (0.1.10)
       cssminify2 (~> 2.0)
       htmlcompressor (~> 0.4)
@@ -41,43 +41,43 @@ GEM
     jekyll-paginate (1.1.0)
     jekyll-redirect-from (0.16.0)
       jekyll (>= 3.3, < 5.0)
-    jekyll-sass-converter (2.1.0)
+    jekyll-sass-converter (2.2.0)
       sassc (> 2.0.1, < 3.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
-    json (2.3.1)
+    json (2.6.2)
     json-minify (0.0.3)
       json (> 0)
-    kramdown (2.3.1)
+    kramdown (2.4.0)
       rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     libv8 (3.16.14.19)
     liquid (4.0.3)
-    listen (3.2.1)
+    listen (3.7.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.4.0)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    public_suffix (4.0.6)
-    rb-fsevent (0.10.4)
+    public_suffix (5.0.0)
+    rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     ref (2.0.0)
     rexml (3.2.5)
-    rouge (3.21.0)
+    rouge (3.30.0)
     safe_yaml (1.0.5)
     sassc (2.4.0)
       ffi (~> 1.9)
-    terminal-table (1.8.0)
+    terminal-table (2.0.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     therubyracer (0.12.3)
       libv8 (~> 3.16.14.15)
       ref
     uglifier (4.2.0)
       execjs (>= 0.3.0, < 3)
-    unicode-display_width (1.7.0)
+    unicode-display_width (1.8.0)
 
 PLATFORMS
   ruby

docker-compose.yml

@@ -1,7 +1,7 @@
 # to start the server just run
 # docker-compose up
 jekyll:
-  image: jekyll/jekyll
+  image: jekyll/jekyll:4.1.0
   command: jekyll serve --watch --incremental --livereload --future
   ports:
     - 4000:4000