Diagrams error: no response received from remote service. With MW 1.35 and

[WolfgangFahl]

env:

• Ubuntu 20.04 LTS
• MediaWiki 1.35 LTS
• PHP 7.4.3

Installed with:

git clone https://github.com/samwilson/diagrams-extension Diagrams

Configured with:

wfLoadExtension( 'Diagrams' );
// The URL at which you installed the Diagrams Service.
$wgDiagramsServiceUrl = 'http://diagrams.bitplan.com';

Tried:

= Example =
<graphviz format='svg'>
digraph g {
  a->b->c
}
</graphviz>

Checked things with a debugger and the service replies but is not asked for the svg format.
There is a proper png response which is somehow ignored.

looks like some of my patched code at https://github.com/WolfgangFahl/diagrams-extension/blob/master/includes/Hooks.php might help.

How can we join that code with the MW 1.34 state that can do local rendering?

[WolfgangFahl]

this is a showstopper and the alternative #22 makes the current state of this extension unusable for me in the target 1.35 LTS environment.