About this extension

THIS IS THE CANARY DISTRIBUTION OF THE METAMASK EXTENSION, INTENDED FOR DEVELOPERS.

MetaMask Flask is a distribution channel of MetaMask Extension for developers, which gives them access to additional unstable APIs. The goal of Flask is to maximize developer control, so that we can learn the full extent of what developers want to do with MetaMask, and later incorporate these lessons into the main MetaMask distribution.

You can find the main / production version of MetaMask here: https://addons.mozilla.org/en-US/firefox/addon/ether-metamask/

MetaMask is an extension for accessing Ethereum enabled distributed applications, or dapps in your browser! The extension injects the Ethereum web3 API into every website’s Javascript context, so that dapps can read from the blockchain.

MetaMask also lets the user create and manage their own identities—via private keys, local client wallet, and hardware wallets like Trezor™. When a dapp wants to perform a transaction and write to the blockchain, the user gets a secure interface to review the transaction, before approving or rejecting it.

Because it adds functionality to the normal browser context, MetaMask requires the permission to read and write to any webpage. You can always “view the source” of MetaMask the way you do any Firefox extension, or view the source code on GitHub:
https://github.com/MetaMask/metamask-extension

MetaMask enables access to:

Web3
Dapps
NFTs
ERC20
tokens
ICOs
ERC271

...and more!

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Release notes for 12.20.0.150

[12.20.0]

Added

Rebrand "Profile syncing" to "Backup and sync", adding a dedicated settings menu and more (#32129)
Show UI error to user if vault should exist, but is missing (#31404)
Add RPC (sub)domain tracking to transaction event metrics for RPC endpoints usage (#32076)
Integrate dynamic content banners (#32101)
Add ability to update remote mode delegations and remove the now redundant "Update to a smart account" step on setup flows (#32713)
Support paying for gas fees using ETH generated by the transaction (#33094)
Introduce a character limit of 20 characters for the total value displayed from simulation results (#33053)
Add a new banner on Send page to show if user has daily allowance and if the remote mode is on (#32884)
feat: ui updates for singlechain swaps behind featureflag (#32699)
feat: Splash screen should be shown for an account only once (#33068)
Add new error message and empty state for Defi tab, Add protocal badge in Defi Details page (#32896)
Add Monad testnet support (#32953)
Specify incoming transaction polling tags to support additional debug in accounts API (#33045)
Add CentraNo1, MMSans and MMPoly font family support to Text component (#31585)
feat: support gas fee tokens via JSON-RPC relay (#32302)
Add a network picker in the asset picker for the send flow (#30959)
Add the 24 hour aggregated price and percent difference on the main wallet view (#32826)
Show totalMaxNetworkFee in Multichain Bridge quote card (#32829)
Add metrics to check rejection of smart account update by user (#32737)
Auto-failover to Quicknode when Infura is down (#31089)

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