It's an offline/online dual purpose wallet for ETHs , Open source.
You only need to download oeww.htm and web3.min.js. (Put together and open with browser)
It can sign transactions offline, let your PC/VM/Smartphone as a big cold wallet;
Or connect to RPC server, using as a super light wallet in a simple way.
In public beta. Full instructions will be released later.
Supports multiple ETH type chains, including ETC, AVAX...
Note: If you need mnemonic code and private key generator,
you can visit this project: BIP39 by iancoleman
It's also an one page solution.