PlantUML rendering or saving fails with CORS error

Question

Any attempt to render a diagram or save gets a long waiting and fails either silently (on render button) or with "Error rendering diagram. Please check your syntax" message.

PlantUml example "class A" is valid and is properly rendered by planttext.com

Console shows CORS error:

"Failed to load resource: the server responded with a status of 503 (Service Unavailable)
macroEditor-1-1-2.html?dialog=1&simpleDialog=1&user_id=_______&user_key=_________&tz=Europe%2FMoscow&loc=en-US&xdm_e=https%3A%2F%2Finsolar.atlassian.net&xdm_c=channel-com.mxgraph.confluence.plugins.plantuml__plantumlcloud&cp=%2Fwiki&xdm_deprecated_addon_key_do_not_use=com.mxgraph.confluence.plugins.plantuml&lic=active&cv=1.296.0:1 Access to XMLHttpRequest at 'https://exp-plant.draw.io/plantuml4/png/Iyv9B2vM22ZDAKvrIIn91000' from origin 'https://plant.draw.io' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource."

Applies for both Chrome and Firefox. For different users.

Any suggestions please?

Thank you

Andy Nightingale_8v770o · Answer

I'm getting the same error when trying to save or preview a PUML drawing in confluence:

Access to XMLHttpRequest at 'https://exp.stratus-addons.com/server-rest-1.2022.14/plantuml/svg' from origin 'https://puml4cc.stratus-addons.com' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: The 'Access-Control-Allow-Origin' header has a value 'https://****.atlassian.net' that is not equal to the supplied origin.

Kirill Ivkushkin · Answer

was fixed so far