This site sits behind Cloudflare CDN/DDOS protection which enforces the ssl encryption mode and it won’t accept very old clients trying to use broken encryption protocols – however I wouldn’t expect this to be a problem for an up to date copy of Avast browser. It could mean there is a proxy in between you and the server which is trying to downgrade the connection or it could be some other issue. You could possibly try reinstalling Avast browser.
I’ll maybe download Avast browser myself on Windows later and see what happens for me.