I don't think it was Electron or even anything based on Chromium - I could be wrong, my memory is fuzzy. But I think they said it was a custom implementation th

I don't think it was Electron or even anything based on Chromium - I could be wrong, my memory is fuzzy. But I think they said it was a custom implementation that predated Electron. Don't quote me on that though. Obviously someone that actually works there would know best. Another financial firm I interviewed at - Tradeweb, also had something similar. Custom implementation, not Electron, but in their case, yes Chromium.