Confirmed.

E.g. Install @nikosdion Akeeba Backup using Isntall from web

Go to /administrator/index.php?option=com_config&view=component&component=com_akeeba

Click Help

Get a popup with url of

https://help.joomla.org/proxy/index.php?keyref=Help37:JHELP_COMPONENTS_com_akeeba_OPTIONS

which is a 404 error page really as the help site has no data for 3rd party extensions.

Ideally extensions xml could have helpUrl published in their xml that could be used, or the help button removed if none available.

As far as I know it is possible for 3rd parties to provide such a help URL (using language strings if I remember right). But it is not that straight forward. I think @chrisdavenport knows more about that system.

See also #6627 and referenced items.

In particular, see https://docs.joomla.org/Help_system/Adding_a_help_button_to_the_toolbar

If that mechanism has stopped working, then it's a bug. Otherwise, it's not.

I wish people would actually read issues before responding.

This is NOT about adding a help button within someone's extension, in their own toolbar

This is about the help button that is rendered on the com_config view, this is a core view

E.g. URL /administrator/index.php?option=com_config&view=component&component=com_akeeba

Therefore the information on the page https://docs.joomla.org/Help_system/Adding_a_help_button_to_the_toolbar is 100% NOT RELEVANT here.

Even with #6627 (comment) I dont see why the help popuop should be proxied through help.joomla.org for custom extensions.

#6627 solved nothing, but still accurately describes the problem.

If I develop a com_whatever, which has a configuration screen powered by com_config, then currently all I can do is append text to this url:

https://help.joomla.org/proxy/index.php?keyref=Help37:

by setting my JHELP_COMPONENTS_COM_WHATEVER_OPTIONS string in my language file.

I cannot make that help button link direct to https://whatever.com/help

#6639 attempted to fix this - but was closed as it broke all core links apparently.

As I said, if that mechanism isn't working, then it's a bug.

Chris, that process works fine everywhere BUT com_config for a component's config, for non core extensions. That's what the old issue and PR tried to address and it's still not fixed.

I have some holiday time coming up so I'll take a look at it then. Unless someone can get to it faster than me.

I think using a helpUrl element in the xml is the way to go. However, if there is no helpUrl element and the translation string is present, a link to local help file(s) should be provided. If there is no translation string at all ... no help button.

I may have some time to see if I can come up with an acceptable implementation.

Excuse any less-than squeaky clean logic or coding, but this is what seems to work okay for my needs:

In config.xml
<config helpURL="http://myserver.net/joomladev/mycomponent/help">
or
<config helpURL="local">

Adjust addToolBar in com_config/view/component/html.php

$helpUrl = (string) $this->form->getXML()->config['helpURL'];
$local = ($helpUrl==='local');
JToolbarHelper::help('JHELP_COMPONENTS_' . $this->currentComponent . '_OPTIONS', $local, ($local?null:$helpUrl), $this->currentComponent);

I guess it just has to check for a component specific string in com_config. That's likely the only issue.

#13286 is the PR for this item.