perf: [startup optimization] defer CookieManager initialization to background thread

[nonproto]

Defer initialization of CookieManager in App.kt from the main thread during Application.onCreate() to a background coroutine (Dispatchers.Default). This optimization removes synchronous initialization of the Chromium WebView engine from the critical startup path, reducing Time to Initial Display (TTID). Includes a thread context switch (withContext(Dispatchers.Main)) for the error fallback toast to ensure it does not crash when called from the background dispatcher.

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PR created automatically by Jules for task 8933816384615012803 started by @nonproto

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[gemini-code-assist]

Code Review

This pull request optimizes app startup by deferring CookieManager initialization to a background coroutine, preventing synchronous file I/O and WebView engine initialization from blocking the main thread. The implementation also ensures that error reporting via Toasts is correctly dispatched to the main thread. A review comment suggests moving the hardcoded error message to string resources to support internationalization.

[nonproto]

/gemini review

[gemini-code-assist]

Code Review

This pull request defers the initialization of CookieManager to a background thread to improve the application's Time to Initial Display (TTID) and replaces a hardcoded error message with a string resource. The reviewer pointed out that moving this initialization breaks the package name spoofing logic in getPackageName(), which currently only inspects the main thread's stack trace, and recommended updating it to check the current thread instead. Additionally, an accidental patch.diff file was included in the PR and should be removed.

[nonproto]

/gemini review

[gemini-code-assist]

Code Review

This pull request defers CookieManager initialization to a background coroutine to improve startup performance and avoid blocking the main thread. It also updates error handling to use string resources and ensures UI updates are executed on the main thread. A review comment suggests removing the fully qualified name for runCatching to improve code readability.

[nonproto]

/gemini review

[gemini-code-assist]

Code Review

This pull request improves app startup performance by deferring CookieManager initialization to a background coroutine, preventing synchronous file I/O from blocking the main thread. Additionally, it replaces a hardcoded error message with a string resource and refines the runCatching syntax. Feedback was provided to prioritize the CookieManager initialization within the background scope and ensure it remains isolated from other startup tasks to prevent scope cancellation.

[nonproto]

/gemini review

[gemini-code-assist]

Code Review

This pull request defers the initialization of CookieManager to a background coroutine in App.kt to avoid blocking the main thread and improve Time to Initial Display (TTID). The reviewer recommends initializing CookieManager on the main thread asynchronously (using Dispatchers.Main) because WebView components are not thread-safe. Additionally, the reviewer points out that a backup file, App.kt.orig, was accidentally committed and should be removed.

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[gemini-code-assist]

Initializing WebView/CookieManager on a background thread (Dispatchers.Default) can lead to crashes or unstable behavior on various Android versions and devices, as WebView components are not thread-safe and generally expect to be initialized on the main thread (with a Looper).

To safely defer the initialization without blocking the critical startup path (maintaining the TTID optimization), you can launch the CookieManager initialization on Dispatchers.Main using a coroutine. Since it is launched asynchronously, it won't block Application.onCreate(), but it will safely run on the main thread.

        ProcessLifecycleOwner.get().lifecycleScope.launch(Dispatchers.Default) {
            launch(Dispatchers.Main) {
                runCatching { CookieManager.getInstance() }
                    .onFailure {
                        Toast.makeText(
                            applicationContext,
                            getString(R.string.information_webview_required),
                            Toast.LENGTH_LONG,
                        ).show()
                    }
            }

References

1. For startup optimizations to improve Time To Initial Display (TTID), use Dispatchers.Default when launching from lifecycleScope. Avoid suspend/await patterns in this context to prevent blocking the main thread, even for I/O operations.

[gemini-code-assist]

It looks like App.kt.orig was accidentally committed. This is a backup file typically created during merge conflict resolution and should be removed from the repository.