##### SUMMARY
The warning that `become` show, point to a non-existing page.

The reference: https://docs.ansible.com/ansible/become.html#becoming-an-unprivileged-user
Should be: https://docs.ansible.com/ansible/user_guide/become.html#risks-of-becoming-an-unprivileged-user

```
  msg: |-
    Failed to set permissions on the temporary files Ansible needs to create when becoming an unprivileged user (rc: 1, err: chown: changing ownership of '/var/tmp/ansible-tmp-1587201990.1515293-106086999273646/': Operation not permitted
    chown: changing ownership of '/var/tmp/ansible-tmp-1587201990.1515293-106086999273646/AnsiballZ_postgresql_db.py': Operation not permitted
    }). For information on working around this, see https://docs.ansible.com/ansible/become.html#becoming-an-unprivileged-user
```

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
become

##### ANSIBLE VERSION
```
ansible 2.9.6
  config file = None
  configured module search path = ['/home/robertdb/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python3.7/site-packages/ansible
  executable location = /usr/local/bin/ansible
  python version = 3.7.6 (default, Jan 30 2020, 09:44:41) [GCC 9.2.1 20190827 (Red Hat 9.2.1-1)]
```

##### CONFIGURATION
```
# empty.
```

##### OS / ENVIRONMENT
Controller: Fedora 31
Managed node: Ubuntu 19

##### STEPS TO REPRODUCE
I use [this](https://github.com/robertdebock/ansible-role-postgres/blob/master/tasks/main.yml#L70) role on Ubuntu 19. (Using [this](https://github.com/robertdebock/ansible-tester) code.

##### EXPECTED RESULTS
The chapter is found immediately.

##### ACTUAL RESULTS
The documentation page loads (good), but does not jump to the right chapter.
pass
            elif sudoable and self._connection.become and become_user:
                expand_path = '~%s' % become_user
            else:
                
                expand_path = '~%s' % (self._get_remote_user() or '')
        
        cmd = self._connection._shell.expand_user(expand_path)
        data = self._low_level_execute_command(cmd, sudoable=False)
        try:
            initial_fragment = data['stdout'].strip().splitlines()[-1]
        except IndexError:
            initial_fragment = None
        if not initial_fragment:
            
            
            cmd = self._connection._shell.pwd()
            pwd = self._low_level_execute_command(cmd, sudoable=False).get('stdout', '').strip()
            if pwd:
                expanded = pwd
            else:
                expanded = path
        elif len(split_path) > 1:
            expanded = self._connection._shell.join_path(initial_fragment, *split_path[1:])
        else:
            expanded = initial_fragment
        if '..' in os.path.dirname(expanded).split('/'):
            raise AnsibleError("'%s' returned an invalid relative home directory path containing '..'" % self._play_context.remote_addr)
        return expanded
    def _strip_success_message(self, data):