Yes, but the app still works on GrapheneOS. They accidentally broke compatibility with the default settings with incorrect anti-tampering code. Disabling the per-app toggle for secure spawning works around it.

We have per-app toggles for exploit protections known to have compatibility issues. Secure spawning wasn't expected to cause any compatibility issues so we didn't have a per-app toggle for it until recently but it's available now.

Yes, but you might have to enable desktop mode on a mobile browser so it doesn't try force-spawning the app.

The app still works too. PayPal just accidentally broke compatibility with secure spawning which can be toggled off per-app. We didn't used to have a per-app toggle since it wasn't expected to cause compatibility issues and it was non-trivial to add support for it, but we have it now.

You can change the link handling in the app settings so it doesn't try to open it via the app. Or open the site in incognito window.

I wish it ran in Firefox on my pc...