The chat transcript reaches the screen through a requestAnimationFrame-gated
flush (useSessionStateCache). The main BrowserWindow never set
backgroundThrottling, so Chromium paused rAF and clamped timers whenever the
window was blurred or occluded -- the live answer would stall until the window
regained focus or the user refreshed. In practice this bit any time Hermes
wasn't the focused window mid-turn (typing in your editor while the agent
replies, detached devtools, another window on top), presenting as "thinking,
no text, have to refresh."
Opt the renderer out of background throttling so a streaming chat app actually
streams in the background:
- backgroundThrottling: false on the main window (matches the secondary
windows that already set it)
- disable-renderer-backgrounding / disable-backgrounding-occluded-windows /
disable-background-timer-throttling at the process level for the
occlusion case
Latent since the desktop app landed (#20059), not a recent regression.
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