I won't bother trying it out if it forces me to use chromium
It seems that your browser doesn't support the new native filesystem API, please use any Chromium 86+ based browser like Chrome, Vivaldi, Edge, etc. Notice that the API doesn't support mobile browsers at the moment.
Logseq: A privacy-first, open-source platform for knowledge management. (github.com)
With everything going on with Twitter and Reddit I feel like I have a new appreciation for having my own local knowledge base on Logseq....