Checklist

• I have checked the issues list
  for similar or identical bug reports.
• I have checked the pull requests list
  for existing proposed fixes.
• I have checked the commit log
  to find out if the bug was already fixed in the master branch.
• I have included all related issues and possible duplicate issues in this issue
  (If there are none, check this box anyway).

Related Issues and Possible Duplicates

Related Issues

• Release 5.0 #6266

Possible Duplicates

• None

Description

Since we migrated to Click, preload options are now using Click's API.
Previously, the used argparse's API.

This breaking change was not properly documented.

Suggestions

We should update our extending user guide and use the correct APIs.