[Regression]: Chromium 155+ aborts a preflighted cross-origin redirect whenever any route is registered (net::ERR_ABORTED)

Finding: In an external report on microsoft/playwright issue 43242, a credentialed, preflighted fetch (custom X-App-Version header) that is redirected cross-origin with a 302 fails with TypeError: Failed to fetch under playwright-core 1.64.0 (Chromium 156.0.8078.4) once any context.route() is registered, even a route that matches nothing; without a route it returns 200 (https://github.com/microsoft/playwright/issues/43242). The reporter also lists 1.65.0-alpha-2026-10-09 as affected and 1.63.0 and earlier (Chromium 153 and older) as unaffected. This is an external report; KFA did not reproduce it. Observed behavior per the reporter: the redirected request ends with net::ERR_ABORTED and canceled true, never reaches the target server, and shows no CORS error or blockedReason. A typical affected pattern is an API answering with a 302 to presigned object-storage downloads while a custom header is sent. Attribution evidence (reporter analysis, not maintainer-confirmed): a binary-swap table shows the failure follows the browser build rather than the playwright-core version. Playwright 1.64.0 with the older 149 binary passed, and 1.61.1 with the 156 binary failed. Chrome for Testing 155.0.8043.0 passed, while 155.0.8047.0 through 157.0.8093.0 failed. Raw CDP with a Fetch.enable whose pattern matches nothing reportedly reproduces the same split, which points at DevTools Fetch interception rather than Playwright routing logic. The reporter suspects a Chromium change, 'OOR-CORS: Avoid CorsURLLoader restart on redirect', which adds the AvoidCorsURLLoaderRestartOnRedirect feature, enabled by default. The confirmed cause is UNKNOWN. Reported mitigation (not verified by KFA): launching with --disable-features=AvoidCorsURLLoaderRestartOnRedirect made the route case pass on Chromium 156. The reporter notes that Playwright's own --disable-features switch is overridden by the last switch, so users may need to restate the whole list. The reporter proposes, as a possible fix, adding the feature to the disabled list in chromiumSwitches.ts, following the BlockOriginHeaderModificationOnRedirect precedent. Status: the issue is closed, but the supplied data shows no maintainer comment, linked commit or release, so closure should not be read as a shipped fix. Fix status is UNKNOWN. Comment coverage may omit middle comments. Reproduction environment details beyond the browser and Playwright versions, such as the OS, were not given.