Gemfile in jekyll-linkpreview-0.6.0 vs Gemfile in jekyll-linkpreview-0.7.0

@@ -1,4 +1,13 @@
 source "https://rubygems.org"
 
 # Specify your gem's dependencies in jekyll-linkpreview.gemspec
 gemspec
+
+# The issue that appraisal 2.4.1 can't work with bundler >= 2.4 was solved
+# (see https://github.com/thoughtbot/appraisal/issues/199 for details),
+# but a new version has not been released yet as of Apr 2023.
+# As it's not possible to install a gem from a git repository in the gemspec file,
+# appraisal is being installed in Gemfile.
+group :development do
+  gem 'appraisal', git: 'https://github.com/thoughtbot/appraisal'
+end