Windows wallet from official site https://beam.mw/downloads/mainnet-windows:
Beam-Wallet-5.3.10410.3657.exe -  16.8 mb

Wallet from github https://github.com/BeamMW/beam-ui/releases/tag/beam-5.3.10410.3657:
Beam-Wallet-5.3.10410.3657.exe - 20 mb

Why? Github wallet was compromised?