Remove some gems

Gemfile

@@ -2,7 +2,6 @@ source 'https://rubygems.org'
 group :jekyll_plugins do
     gem 'jekyll'
     gem 'jekyll-archives'
-    gem 'jekyll-diagrams'
     gem 'jekyll-email-protect'
     gem 'jekyll-feed'
     gem 'jekyll-github-metadata'
@@ -10,8 +9,6 @@ group :jekyll_plugins do
     gem 'jekyll-paginate-v2'
     gem 'jekyll-sitemap'
     gem 'jekyll-target-blank'
-    gem 'jekyll-twitter-plugin'
-    gem 'jekyll-redirect-from'
     gem 'jemoji'
     gem 'unicode_utils'
     gem 'webrick'

_config.yml

@@ -124,10 +124,8 @@ keep_files:
   - .nojekyll
   - .git
 
-# Plug-ins
 plugins:
   - jekyll-archives
-  - jekyll-diagrams
   - jekyll-email-protect
   - jekyll-feed
   - jekyll-github-metadata
@@ -135,32 +133,25 @@ plugins:
   - jekyll-paginate-v2
   - jekyll-sitemap
   - jekyll-target-blank
-  - jekyll-twitter-plugin
   - jemoji
 
-# Sitemap settings
 defaults:
   - scope:
       path:            "assets/**/*.*"
     values:
       sitemap:         false
-# Extras
 github: [metadata]
 
 # -----------------------------------------------------------------------------
 # Jekyll optimization
 # -----------------------------------------------------------------------------
 
-# HTML remove comments (<!-- .... -->)
 remove_HTML_comments: false
 
-# HTML beautifier (_plugins/beautify.rb) / https://github.com/threedaymonk/htmlbeautifier
-beautify: false # This function has conflict with the code snippets, they can be displayed incorrectly
+beautify: false
 
-# HTML minify (_plugins/minify.rb) Thanks to: https://www.ffbit.com/blog/2021/03/17/html-minification-in-jekyll.html
 minify: false
 
-# CSS/SASS minify
 sass:
   style: compressed
 
@@ -169,7 +160,7 @@ sass:
 # -----------------------------------------------------------------------------
 
 jekyll-archives:
-  enabled: [year, tags, categories] # enables year, tag and category archives (remove if you need to disable one of them). 
+  enabled: [year, tags, categories]
   layouts:
     year: archive-year
     tag: archive-tag