From the UI perspective, creating an Issue with the name "placeholder for pull request" and instantly changing it to a PR with the commit title works fine. However, tools using the GitHub API to listen for "Issue/PR Created" events will use the placeholder, such as this Slack app

This request is to use the GitHub API to make a PR with the commit title (first line of commit message) as the PR title initially, instead of updated it after. Again, from the GitHub.com UI perspective this is fine, but it tricks GitHub Apps listening for PR Created events