##### 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.
raise AnsibleError("unknown encoding in content option, failed: %s" % to_native(dest_result))
                    diff['before_header'] = destination
                    diff['before'] = to_text(dest_contents)
            if source_file:
                st = os.stat(source)
                if C.MAX_FILE_SIZE_FOR_DIFF > 0 and st[stat.ST_SIZE] > C.MAX_FILE_SIZE_FOR_DIFF:
                    diff['src_larger'] = C.MAX_FILE_SIZE_FOR_DIFF
                else:
                    display.debug("Reading local copy of the file %s" % source)
                    try:
                        with open(source, 'rb') as src:
                            src_contents = src.read()
                    except Exception as e:
                        raise AnsibleError("Unexpected error while reading source (%s) for diff: %s " % (source, to_native(e)))
                    if b"\x00" in src_contents:
                        diff['src_binary'] = 1
                    else:
                        diff['after_header'] = source
                        diff['after'] = to_text(src_contents)
            else:
                display.debug(u"source of file passed in")
                diff['after_header'] = u'dynamically generated'
                diff['after'] = source
        if self._play_context.no_log:
            if 'before' in diff:
                diff["before"] = u""
            if 'after' in diff:
                diff["after"] = u" [[ Diff output has been hidden because 'no_log: true' was specified for this result ]]\n"
        return diff
    def _find_needle(self, dirname, needle):