What is more, I think it's buggy. It fails to load some icons when I run it from Firefox.

I'm annoyed at how irrational and badly managed some products of Google are. For example, they had a great standards-compliant chat, Google Talk, and they turned it into the mess Hangouts is. Not happy with that, they built the competing Duo and Allo.

I totally agree with you. Whoever approves or decides on UI at Google has no taste whatsoever.