It's not actually Electron; it's a bit of an unholy mishmash of webkit doing layout of things that are sometimes native views with interaction handling that's also a bit of both. It just has many of the same problems that that Electron apps have, which is also why the interactions are so janky.
So it’s like those late 90s ActiveX IE iframes in Windows programs all over again? That sucks. iTunes did seem to have some of it too in the Store section.