title: Run MR pipeline on “Run pipeline” button
body: <p>We use an on-prem GitLab server. One of the rules for launching our MR pipeline is its state. It should not be <strong>Draft</strong> or <strong>WIP</strong>, as I stated below.</p>
  <pre><code>  rules:
    - if: $CI_MERGE_REQUEST_TITLE =~ /^WIP/ || $CI_MERGE_REQUEST_TITLE =~ /^Draft/
      when: never
    - if: '$CI_PIPELINE_SOURCE == &quot;merge_request_event&quot;'
    - if: '$CI_PIPELINE_SOURCE == &quot;web&quot;'
  </code></pre>
  <p>But in this form, it does not start in all cases with the error: “<strong>No stages/jobs for this pipeline</strong>”. Our developers want the MR pipeline to start when you click on the “<strong>Run pipeline</strong>” button in the “pipelines” section of the current MR. I did not find any indicator for clicking on this button, neither in the webhook nor anywhere else. I tried to use only <code>when: manual</code>, <code>if: '$CI_PIPELINE_SOURCE == &quot;web&quot;</code> and many other rules, but still no luck. Is there a way to make an exception to run the pipeline in this case, but keep it for the rest?</p>