Live-resize frame lag: the native window surface resizes before the
compositor has a frame at the new size; the gap showed Electron's
default WHITE window background — glaring on a dark app, at the edges
on shrink. The standard treatment, all three:
- BrowserWindow backgroundColor '#141414' fills the lag with the app bg
- show: false + ready-to-show — the window appears only after the page
has rendered (kills the first-paint white window)
- color-scheme: dark — native widgets and scrollbars render dark
Owner resize-verified in the Electron dev shell.