Penpot might be a good alternative for Figma. It is OSS and has plugin support. Prob quite feasible to consider a plugin that utilizes Nostr as backend for comments.
We are working on an idea how to build SAAS business apps on top of Nostr. The idea is to rebuild apps like Slack, Notion, Figma, Github, Linear on single Nostr relay and Nostr standard that would allow some cool things like seamless cross-app messaging (e.g. like Slack <> Linear), cross-app workflows.
Here is PDF with more details.: https://drive.google.com/file/d/1U_bC4AmR2_61GwgiShNv_EctOcyh4u7A/view?usp=drive_link
If anybody is working on something similar or like the idea and want to join our efforts, please let me know.
Discussion
Thanks for the tip. I will add it to my list of apps that we should pitch or directly help to integrate with Nostr for Business.