My slide

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "reveal.js"]
-	path = reveal.js
-	url = https://github.com/hakimel/reveal.js.git

Gemfile

@@ -1,5 +1,5 @@
 source "https://rubygems.org"
 
-gem 'github-pages', '>= 198'
-gem 'html-proofer', '>= 3.11.1'
+gem 'github-pages', '>= 207'
+gem 'html-proofer', '>= 3.13.0'
 gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw]

Gemfile.lock

@@ -1,11 +1,12 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (4.2.11.1)
-      i18n (~> 0.7)
+    activesupport (6.0.3.6)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
       minitest (~> 5.1)
-      thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
+      zeitwerk (~> 2.2, >= 2.2.2)
     addressable (2.7.0)
       public_suffix (>= 2.0.2, < 5.0)
     coffee-script (2.4.1)
@@ -15,76 +16,82 @@ GEM
     colorator (1.1.0)
     commonmarker (0.17.13)
       ruby-enum (~> 0.5)
-    concurrent-ruby (1.1.5)
-    dnsruby (1.61.3)
-      addressable (~> 2.5)
-    em-websocket (0.5.1)
+    concurrent-ruby (1.1.8)
+    dnsruby (1.61.5)
+      simpleidn (~> 0.1)
+    em-websocket (0.5.2)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
-    ethon (0.12.0)
-      ffi (>= 1.3.0)
+    ethon (0.13.0)
+      ffi (>= 1.15.0)
     eventmachine (1.2.7)
     execjs (2.7.0)
-    faraday (0.17.0)
+    faraday (1.4.1)
+      faraday-excon (~> 1.1)
+      faraday-net_http (~> 1.0)
+      faraday-net_http_persistent (~> 1.1)
       multipart-post (>= 1.2, < 3)
-    ffi (1.11.1)
+      ruby2_keywords (>= 0.0.4)
+    faraday-excon (1.1.0)
+    faraday-net_http (1.0.1)
+    faraday-net_http_persistent (1.1.0)
+    ffi (1.15.0)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
-    github-pages (201)
-      activesupport (= 4.2.11.1)
-      github-pages-health-check (= 1.16.1)
-      jekyll (= 3.8.5)
-      jekyll-avatar (= 0.6.0)
+    github-pages (214)
+      github-pages-health-check (= 1.17.0)
+      jekyll (= 3.9.0)
+      jekyll-avatar (= 0.7.0)
       jekyll-coffeescript (= 1.1.1)
       jekyll-commonmark-ghpages (= 0.1.6)
       jekyll-default-layout (= 0.1.4)
-      jekyll-feed (= 0.11.0)
+      jekyll-feed (= 0.15.1)
       jekyll-gist (= 1.5.0)
-      jekyll-github-metadata (= 2.12.1)
-      jekyll-mentions (= 1.4.1)
-      jekyll-optional-front-matter (= 0.3.0)
+      jekyll-github-metadata (= 2.13.0)
+      jekyll-mentions (= 1.6.0)
+      jekyll-optional-front-matter (= 0.3.2)
       jekyll-paginate (= 1.1.0)
-      jekyll-readme-index (= 0.2.0)
-      jekyll-redirect-from (= 0.14.0)
-      jekyll-relative-links (= 0.6.0)
-      jekyll-remote-theme (= 0.4.0)
+      jekyll-readme-index (= 0.3.0)
+      jekyll-redirect-from (= 0.16.0)
+      jekyll-relative-links (= 0.6.1)
+      jekyll-remote-theme (= 0.4.3)
       jekyll-sass-converter (= 1.5.2)
-      jekyll-seo-tag (= 2.5.0)
-      jekyll-sitemap (= 1.2.0)
-      jekyll-swiss (= 0.4.0)
+      jekyll-seo-tag (= 2.7.1)
+      jekyll-sitemap (= 1.4.0)
+      jekyll-swiss (= 1.0.0)
       jekyll-theme-architect (= 0.1.1)
       jekyll-theme-cayman (= 0.1.1)
       jekyll-theme-dinky (= 0.1.1)
-      jekyll-theme-hacker (= 0.1.1)
+      jekyll-theme-hacker (= 0.1.2)
       jekyll-theme-leap-day (= 0.1.1)
       jekyll-theme-merlot (= 0.1.1)
       jekyll-theme-midnight (= 0.1.1)
       jekyll-theme-minimal (= 0.1.1)
       jekyll-theme-modernist (= 0.1.1)
-      jekyll-theme-primer (= 0.5.3)
+      jekyll-theme-primer (= 0.5.4)
       jekyll-theme-slate (= 0.1.1)
       jekyll-theme-tactile (= 0.1.1)
       jekyll-theme-time-machine (= 0.1.1)
-      jekyll-titles-from-headings (= 0.5.1)
-      jemoji (= 0.10.2)
-      kramdown (= 1.17.0)
-      liquid (= 4.0.0)
-      listen (= 3.1.5)
+      jekyll-titles-from-headings (= 0.5.3)
+      jemoji (= 0.12.0)
+      kramdown (= 2.3.1)
+      kramdown-parser-gfm (= 1.1.0)
+      liquid (= 4.0.3)
       mercenary (~> 0.3)
-      minima (= 2.5.0)
+      minima (= 2.5.1)
       nokogiri (>= 1.10.4, < 2.0)
-      rouge (= 3.11.0)
+      rouge (= 3.26.0)
       terminal-table (~> 1.4)
-    github-pages-health-check (1.16.1)
+    github-pages-health-check (1.17.0)
       addressable (~> 2.3)
       dnsruby (~> 1.60)
       octokit (~> 4.0)
-      public_suffix (~> 3.0)
+      public_suffix (>= 2.0.2, < 5.0)
       typhoeus (~> 1.3)
-    html-pipeline (2.12.0)
+    html-pipeline (2.14.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    html-proofer (3.13.0)
+    html-proofer (3.14.1)
       addressable (~> 2.3)
       mercenary (~> 0.3)
       nokogiri (~> 1.10)
@@ -95,21 +102,21 @@ GEM
     http_parser.rb (0.6.0)
     i18n (0.9.5)
       concurrent-ruby (~> 1.0)
-    jekyll (3.8.5)
+    jekyll (3.9.0)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
       i18n (~> 0.7)
       jekyll-sass-converter (~> 1.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 1.14)
+      kramdown (>= 1.17, < 3)
       liquid (~> 4.0)
       mercenary (~> 0.3.3)
       pathutil (~> 0.9)
       rouge (>= 1.7, < 4)
       safe_yaml (~> 1.0)
-    jekyll-avatar (0.6.0)
-      jekyll (~> 3.0)
+    jekyll-avatar (0.7.0)
+      jekyll (>= 3.0, < 5.0)
     jekyll-coffeescript (1.1.1)
       coffee-script (~> 2.2)
       coffee-script-source (~> 1.11.1)
@@ -122,36 +129,37 @@ GEM
       rouge (>= 2.0, < 4.0)
     jekyll-default-layout (0.1.4)
       jekyll (~> 3.0)
-    jekyll-feed (0.11.0)
-      jekyll (~> 3.3)
+    jekyll-feed (0.15.1)
+      jekyll (>= 3.7, < 5.0)
     jekyll-gist (1.5.0)
       octokit (~> 4.2)
-    jekyll-github-metadata (2.12.1)
-      jekyll (~> 3.4)
+    jekyll-github-metadata (2.13.0)
+      jekyll (>= 3.4, < 5.0)
       octokit (~> 4.0, != 4.4.0)
-    jekyll-mentions (1.4.1)
+    jekyll-mentions (1.6.0)
       html-pipeline (~> 2.3)
-      jekyll (~> 3.0)
-    jekyll-optional-front-matter (0.3.0)
-      jekyll (~> 3.0)
+      jekyll (>= 3.7, < 5.0)
+    jekyll-optional-front-matter (0.3.2)
+      jekyll (>= 3.0, < 5.0)
     jekyll-paginate (1.1.0)
-    jekyll-readme-index (0.2.0)
-      jekyll (~> 3.0)
-    jekyll-redirect-from (0.14.0)
-      jekyll (~> 3.3)
-    jekyll-relative-links (0.6.0)
-      jekyll (~> 3.3)
-    jekyll-remote-theme (0.4.0)
+    jekyll-readme-index (0.3.0)
+      jekyll (>= 3.0, < 5.0)
+    jekyll-redirect-from (0.16.0)
+      jekyll (>= 3.3, < 5.0)
+    jekyll-relative-links (0.6.1)
+      jekyll (>= 3.3, < 5.0)
+    jekyll-remote-theme (0.4.3)
       addressable (~> 2.0)
-      jekyll (~> 3.5)
-      rubyzip (>= 1.2.1, < 3.0)
+      jekyll (>= 3.5, < 5.0)
+      jekyll-sass-converter (>= 1.0, <= 3.0.0, != 2.0.0)
+      rubyzip (>= 1.3.0, < 3.0)
     jekyll-sass-converter (1.5.2)
       sass (~> 3.4)
-    jekyll-seo-tag (2.5.0)
-      jekyll (~> 3.3)
-    jekyll-sitemap (1.2.0)
-      jekyll (~> 3.3)
-    jekyll-swiss (0.4.0)
+    jekyll-seo-tag (2.7.1)
+      jekyll (>= 3.8, < 5.0)
+    jekyll-sitemap (1.4.0)
+      jekyll (>= 3.7, < 5.0)
+    jekyll-swiss (1.0.0)
     jekyll-theme-architect (0.1.1)
       jekyll (~> 3.5)
       jekyll-seo-tag (~> 2.0)
@@ -161,8 +169,8 @@ GEM
     jekyll-theme-dinky (0.1.1)
       jekyll (~> 3.5)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-hacker (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-hacker (0.1.2)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
     jekyll-theme-leap-day (0.1.1)
       jekyll (~> 3.5)
@@ -179,8 +187,8 @@ GEM
     jekyll-theme-modernist (0.1.1)
       jekyll (~> 3.5)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-primer (0.5.3)
-      jekyll (~> 3.5)
+    jekyll-theme-primer (0.5.4)
+      jekyll (> 3.5, < 5.0)
       jekyll-github-metadata (~> 2.9)
       jekyll-seo-tag (~> 2.0)
     jekyll-theme-slate (0.1.1)
@@ -192,45 +200,51 @@ GEM
     jekyll-theme-time-machine (0.1.1)
       jekyll (~> 3.5)
       jekyll-seo-tag (~> 2.0)
-    jekyll-titles-from-headings (0.5.1)
-      jekyll (~> 3.3)
+    jekyll-titles-from-headings (0.5.3)
+      jekyll (>= 3.3, < 5.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
-    jemoji (0.10.2)
+    jemoji (0.12.0)
       gemoji (~> 3.0)
       html-pipeline (~> 2.2)
-      jekyll (~> 3.0)
-    kramdown (1.17.0)
-    liquid (4.0.0)
-    listen (3.1.5)
-      rb-fsevent (~> 0.9, >= 0.9.4)
-      rb-inotify (~> 0.9, >= 0.9.7)
-      ruby_dep (~> 1.2)
+      jekyll (>= 3.0, < 5.0)
+    kramdown (2.3.1)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
+    liquid (4.0.3)
+    listen (3.5.1)
+      rb-fsevent (~> 0.10, >= 0.10.3)
+      rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.3.6)
-    mini_portile2 (2.4.0)
-    minima (2.5.0)
-      jekyll (~> 3.5)
+    mini_portile2 (2.5.1)
+    minima (2.5.1)
+      jekyll (>= 3.5, < 5.0)
       jekyll-feed (~> 0.9)
       jekyll-seo-tag (~> 2.1)
-    minitest (5.12.2)
+    minitest (5.14.4)
     multipart-post (2.1.1)
-    nokogiri (1.10.4)
-      mini_portile2 (~> 2.4.0)
-    octokit (4.14.0)
+    nokogiri (1.11.4)
+      mini_portile2 (~> 2.5.0)
+      racc (~> 1.4)
+    octokit (4.20.0)
+      faraday (>= 0.9)
       sawyer (~> 0.8.0, >= 0.5.3)
-    parallel (1.18.0)
+    parallel (1.19.0)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    public_suffix (3.1.1)
+    public_suffix (4.0.6)
+    racc (1.5.2)
     rainbow (3.0.0)
-    rb-fsevent (0.10.3)
-    rb-inotify (0.10.0)
+    rb-fsevent (0.10.4)
+    rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rouge (3.11.0)
-    ruby-enum (0.7.2)
+    rexml (3.2.5)
+    rouge (3.26.0)
+    ruby-enum (0.9.0)
       i18n
-    ruby_dep (1.5.0)
-    rubyzip (2.0.0)
+    ruby2_keywords (0.0.4)
+    rubyzip (2.3.0)
     safe_yaml (1.0.5)
     sass (3.7.4)
       sass-listen (~> 4.0.0)
@@ -240,23 +254,29 @@ GEM
     sawyer (0.8.2)
       addressable (>= 2.3.5)
       faraday (> 0.8, < 2.0)
+    simpleidn (0.2.1)
+      unf (~> 0.1.4)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     thread_safe (0.3.6)
-    typhoeus (1.3.1)
+    typhoeus (1.4.0)
       ethon (>= 0.9.0)
-    tzinfo (1.2.5)
+    tzinfo (1.2.9)
       thread_safe (~> 0.1)
-    unicode-display_width (1.6.0)
+    unf (0.1.4)
+      unf_ext
+    unf_ext (0.0.7.7)
+    unicode-display_width (1.7.0)
     yell (2.2.0)
+    zeitwerk (2.4.2)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
-  github-pages (>= 198)
-  html-proofer (>= 3.11.1)
+  github-pages (>= 207)
+  html-proofer (>= 3.13.0)
   tzinfo-data
 
 BUNDLED WITH
-   1.17.3
+   2.2.9

_config.yml

@@ -1,7 +1,7 @@
 timezone:    Europe/Berlin
 future:      false
 # Set baseurl to the base path of the site eg "/mytalk"
-baseurl:     "/github-slideshow"
+# baseurl:     "/github-slideshow"
 # The allowed values are 'rouge', 'pygments' or null.
 highlighter: rouge
 # markdown - Valid options are [ maruku | rdiscount | kramdown | redcarpet ]