PR commits do not start

I’m new to Drone so please excuse me if my question is silly. Some links below due to the new users restriction.

I use Drone for Gitea, and we have Drone running very well for one repository([1]). Now I set up Drone as pure syntax check for another repository ([2]) and it does work for direct commits to master but not for open Pull Requests.

As a comparison I opened a test PR for the “good repo” (link) and one for the “bad repo” (link). In the first it works (Drone output [3]), in the latter it doesn’t start the syntax check (see Drone [4]).

As comparison, here the two .drone.yml files:

pipeline:
  quality:
    image: williamyeh/ansible:debian8
    commands:
        - ansible-playbook -vvv playbook.yml -i hosts --syntax-check

  syntaxcheck:
    image: publysher/hugo
    commands:
        - cd site; ./build/build.sh syntax

  deploy:
    image: williamyeh/ansible:debian8
    secrets: [ ssh_key ]
    commands:
      - mkdir /root/.ssh && echo "$SSH_KEY" > /root/.ssh/id_rsa && chmod 0600 /root/.ssh/id_rsa
      - ssh-keyscan -H lund.fsfeurope.org >> ~/.ssh/known_hosts
      - ansible-playbook playbook.yml -i hosts
    when:
       event: [push, pull_request, tag, deployment]
       branch: master

Non-working repo:

    pipeline:
      syntaxcheck:
        image: vsasyan/xmllint
        commands:
            - find . -type f \( -iname "*.xhtml" -o -iname "*.xml" -o -iname "*.xsl" \) -exec xmllint --noout {} +

What’s wrong with the second configuration?

Thanks for your help in advance!

[1] https://git.fsfe.org/pmpc/website
[2] https://git.fsfe.org/FSFE/fsfe-website/
[3] https://drone.fsfe.org/pmpc/website/5331
[4] https://drone.fsfe.org/FSFE/fsfe-website

I recommend looking at your drone server logs with DRONE_DEBUG=true ? The server writes a detailed log message for any hook that it receives that it fails to process or ignores.