If you have installed Jekyll in WSL2 Ubuntu via apt-get then you might end up with this error:

undefined method `delegate_method_as' for Jekyll::Drops::CollectionDrop:Class (NoMethodError)

Here is the quick fix:

PACKAGES="$(dpkg -l |grep jekyll|cut -d" " -f3|xargs )"
sudo apt remove --purge $PACKAGES
sudo apt autoremove
sudo gem install jekyll jekyll-feed jekyll-gist jekyll-paginate jekyll-sass-converter jekyll-coffeescript
bundle update

If you encounter this error when running gem install:

ERROR:  While executing gem ... (ArgumentError)
    wrong number of arguments (given 4, expected 1)

You can use this fix:

gem uninstall psych
gem install activesupport -v '6.0.4.1' --source 'https://rubygems.org/'