How Many Bits of Pi?Apparently all Raspberry Pi CPUs show up the same in the Linux kernel, so you have to look at the actual hardware to verify what processor you're running on and whether it's 32 or 64-bit.
Install Vivaldi on Arch Linux for Arm64If you don't want to use Flatpak or Snap, here's how you can modify an AUR package for x86_64 to build an Arm64 package for Arch.