WhatsApp for Pixel

This is usually because heads-up (pop-up) alerts are turned off for that notification category. Go to Settings, Apps, WhatsApp, Notifications, tap the Messages category, and make sure it is set to Default (or higher) with Pop on screen enabled rather than Silent. Next, open Settings, Apps, WhatsApp, App battery usage and choose Unrestricted so Android does not throttle WhatsApp in the background. Also check that Do Not Disturb is off or that WhatsApp is allowed through it. A reboot after these changes usually restores the pop-up alerts and sound. See how others solved this on Reddit

If your old phone is also Android, install WhatsApp on the Pixel, verify your number, and use Restore from Google Drive. First back up on the old phone via WhatsApp, three dots, Settings, Chats, Chat backup using the same Google account, then sign into that same account on the Pixel. If you are moving from an iPhone, use WhatsApp's built-in Move iOS chats feature during Pixel setup with a USB-C to Lightning cable, since iPhone backups live in iCloud and cannot be restored to Android otherwise. See how others solved this on Reddit

First update WhatsApp itself from the Play Store, then clear its cache via Settings, Apps, WhatsApp, Storage and cache, Clear cache (not Clear storage, which deletes data). If problems persist, confirm WhatsApp is set to Unrestricted under Settings, Apps, WhatsApp, App battery usage so Adaptive Battery and Doze restrictions are not killing it in the background. Restarting the phone after the update often clears lingering glitches too. See how others solved this on Reddit

This is Android's Conversation notification style, which enlarges the sender's photo. To make it compact again, long-press a WhatsApp notification, tap the gear or Settings, find the entry under the Conversations section, and set it to Default instead of Priority (Priority is what adds the large avatar and bubble). You can also turn off Bubbles under Settings, Apps, WhatsApp, Notifications, Bubbles if floating chat heads are appearing. See how others solved this on Reddit

Increase the system scaling in Settings, Display and touch (or Display), Display size and text, then drag the Display size slider up, which enlarges WhatsApp's interface and chat list. You can independently raise Font size in the same menu for larger text everywhere. WhatsApp also has its own Settings, Chats, Font size option with a Large setting that affects message text inside chats. See how others solved this on Reddit

Pixel's stock Android has no built-in app cloning feature like Samsung or Xiaomi, so you cannot clone the app itself. However, WhatsApp now supports two numbers natively: open WhatsApp, tap the three dots or your profile arrow at the top, choose Add account, and add a second number with its own SIM or eSIM. This gives you dual WhatsApp without any third-party cloning app. See how others solved this on Reddit