I can do this from my command line:
$ ipfs swarm connect /dnsaddr/ipfs-nodes.cluster.ipfs.io
But not from Web UI. Let's fix this.

@lidel -- per our conversation 😊 We can discuss in next triage meeting.
We need to see if updating to latest is-ipfs is enough.
If not, we need to pic up https://github.com/multiformats/js-multiaddr/issues/94 and finish adding full support for `/dnsaddr.
Updating is-ipfs didn't work @lidel
Guess we need to add full support for /dnsaddr
Kicked-off discussion in https://github.com/multiformats/js-multiaddr/issues/94#issuecomment-682497762
Fixed in https://github.com/multiformats/js-multiaddr/pull/149, we need to switch to the latest version of js-multiaddr lib and see if it "just works"
update: confirmed that it works with fix from https://github.com/ipfs-shipyard/is-ipfs/pull/35 → we need to merge & ship that first, then switch ipfs-webui to that + bump multiaddr here too