SVG exports show as black boxes

[jpmeyer01]

Hi,
I am running Flows for APEX 23.1 on APEX 23.2.
When I export a diagram as SVG, all workflow diagram elements show as black boxes.
Only text annotations show correctly.
I have tried to open the svg files with Chrome, Firefox and even Gimp ... always the same result ;-(
Is there a trick that I missed?
Please find example attached.
Regards,
J.-P.

[jpmeyer01]

I have found out some more ...
When I trigger the SVG export in flow viewer by clicking the icon with the landscape picture, I get the result described above.
However, if am in "Modify Diagram" mode and then trigger the SVG export from the burger menu, the result is correct.
Could that be a bug?
Regards,
J.-P.