The white disc indicating a text on the envelope, stating that it is inflated with a gas lighter than air (He).
But the article below indicates:
HyLight will be able to develop hydrogen airships on an industrial scale to explore infrastructures in zero-emissions fashion.
The name ‘HyLighter’ seems to suggest a view on hydrogen, but certainly in the future due to regulatory issues related to the danger of flammability.
If this problem is solved, then perhaps some AWE (in addition to those of the airship) doors could open, but nothing is less certain.