101Domain.com (an advertiser here) put together a database of registries that are providing some form of relief during the current Covid-19 pandemic.
In a blog post they lay out all the info:
As part of our effort, we work closely together with the various domain name registries around the world, which are adjusting their policies to help customers during these challenging times. Some registries have provided relief in various ways for those who are having difficulties including:
No restore fee for selected domain renewals past the expiration timePrice reduction for specific domain extensions
Temporary discounts on certain renewal fees