Lanes disappear in demo.bpmn.io but work in bpmn-io Chrome extension

I am trying to use the following diagram in bpmn.io: Sourcing_multi_lane (1).bpmn (13.1 KB). However the behaviour is not consistent between the latest releases and the Chrome plugin (which I am not using, but I wanted to compare with an older version of bpmn-io.

On https://demo.bpmn.io/ all the lanes disappear and only the “content” is displayed:

While using the outdated bpmn-io Chrome plugin, everything seems to work:

Can you please help me clarify what the issue may be?

Thanks!

Some of the IDs in your diagram start with a number and are therefore nod valid according to the XML specification. We started validating IDs a while ago which is why the diagram cannot be imported without warnings in newer versions of bpmn-js.