Username popups

[themeone]

When I use Twitter in Vivaldi, you can hover over a username and get a popup of information (basically the user's Twitter "bio").

This doesn't happen in SeaMonkey. Is this something I can enable, or is it something SeaMonkey just doesn't support?

[raj_bhaskar]

This used to work in SM. I'd noticed that it had stopped working recently, but hadn't realised it was still working in other browsers. I tried setting a useragent override to FF68 but that didn't help. There are a number of errors in the JS console that look like they might be related.