I've tried it in a couple different browsers and it works well.
Also, I like the concept of 'open source' as it brings together a unique talent of users and programmers (i.e. plugins, instruments, filters, etc), while providing those with 'newbie' skills a resource to look to.
I would definitely fund this project.
Thanks for the extensive tests! Good to hear, I've tested Chromium, Firefox and iOS Safari so far only.
If you want to help the project, there is actually a funding page here (hope this is OK to post on HN, I'm not very experienced): https://seven.systems/xequence-audio/