I suspect (without actually having tried it myself, but based on dummy keyboard tests when developing my own designs) that what looks good and obvious in terms of those thumb clusters, is not so practical given the angle that our thumbs operate at. This unsubstantiated opinion (:-)) applies to Maltron and children (Kinesis and ErgoDox). But lots of people swear by those layouts so maybe I'm wrong.. :-)
The problem is the main thumb keys are long, which obstruct the other keys. This is okay for independent utility keys, but not for combination rolling with fingers, especially when speed and accuracy is involved. Big keys also affect the impact point of striking a key. It feels weird to hit a key other than at the center.
Instead, they can split the big keys into smaller keys. This should improve rolling with fingers and provides extra keys for the thumbs.
You use Vivaldi, right? Which is Chromium in disguise... which is (back to roots) based on KHTML. At the moment local versions of KLA do not work in either Chromium or Konqueror (using either of the two supported render engines). The page loads without text. So I thought it was font-related... Firefox say the site uses Lato, pulled in via Google font api. Don't have it installed locally (strangely enough... only Noto family). But I can't figure out why Firefox has no trouble but my other two browsers don't work.
there's something about enabling cross-server scripts for local servers.