Cannot verify ETH address with MetaMask

Pressing the "Add through Metamask" button shows the following errors in the debug console:

Using:
- Chromium 84.0.4128.0
- MetaMask 7.7.9

```
Error verifying account Error: [ethjs-query] while formatting inputs '[[{"type":"string","name":"Message","value":"By signing this transaction, I prove my ownership of account undefined"}],null]' for method 'signTypedData' error: Error: [ethjs-format] hex string 'undefined' must be an alphanumeric 42 utf8 byte hex (chars: a-fA-F) string, is 0 bytes
(anonymous) @ angular.min.jsm?_=b3c648fe3ec22e9f96bb9807:89
```
```
Error when validating ETH addrs Error: Error verifying account Error: [ethjs-query] while formatting inputs '[[{"type":"string","name":"Message","value":"By signing this transaction, I prove my ownership of account undefined"}],null]' for method 'signTypedData' error: Error: [ethjs-format] hex string 'undefined' must be an alphanumeric 42 utf8 byte hex (chars: a-fA-F) string, is 0 bytes
(anonymous) @ angular.min.jsm?_=b3c648fe3ec22e9f96bb9807:89
```