I have stored a multiline environnement variable thanks to github docs.
- name: copy
  run: |
     echo 'CONTENT_ENV<<EOF' >> $GITHUB_ENV
     cat README.md >> $GITHUB_ENV
     echo 'EOF' >> $GITHUB_ENV
I would like to get it, but this code give one line :
 - name: paste
   run: echo $CONTENT_ENV > index.md
The worflow shows the variable properly stored in env (with spaces) :

 
     
    