add documentation explaining what's going on with the zoomfactor broadcast

sawka · sawka · commit f62b47e62a4a · 2026-03-06T10:18:51.000-08:00
diff --git a/emain/emain-util.ts b/emain/emain-util.ts
@@ -12,6 +12,12 @@ const MinZoomLevel = 0.4;
 const MaxZoomLevel = 2.6;
 const ZoomDelta = 0.2;
 
+// Note: Chromium automatically syncs zoom factor across all WebContents
+// sharing the same origin/session, so we only need to notify renderers
+// to update their CSS/state — not call setZoomFactor on each one.
+// We broadcast to all WebContents (including devtools, webviews, etc.) but
+// that is safe because "zoom-factor-change" is a custom app-defined event
+// that only our renderers listen to; unrecognized IPC messages are ignored.
 function broadcastZoomFactorChanged(newZoomFactor: number): void {
     for (const wc of electron.webContents.getAllWebContents()) {
         if (wc.isDestroyed()) {
