MetaMask Legacy Web3

Adds MetaMask's legacy window.web3 API to your browser
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The MetaMask Legacy Web3 Chrome extension reinstates the deprecated window.web3 API previously provided by MetaMask. Although MetaMask stopped injecting window.web3 in December 2020 to boost security and performance, this change can disrupt older or unmaintained decentralized websites and applications (dApps).

By adding this extension alongside your MetaMask wallet, you regain compatibility with those legacy dApps without sacrificing the convenience of MetaMask. It ensures seamless interaction with blockchain sites that still rely on the legacy API, preserving accessibility to older Ethereum-based services without compromising security improvements.

Manifest V2 Cryptocurrency Privacy & Security Developer Tools
By:
danfinlay
Daily users:
1,602+ 29
Rating:
4.32
(161) 1 new ratings
Version:
1.0.2 Last updated: 2021-01-19
Version code:
5165454
Creation date:
2020-12-10
Risk:
Moderate risk impact Low risk likelihood
Size:
99.63K
Email:
su*****@metamask.io
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Firefox Browser Add-ons
Updated:
a day ago

Ranking

# 2,368 ▼ 5
Other rankings
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User reviews

Users have a positive impression of the MetaMask Legacy Web3 Firefox add-on, praising it as a great app and expressing high satisfaction. No specific issues or drawbacks are reported by multiple users in the reviews provided.
Pros
  • Users appreciate the overall quality and functionality of the app.
  • The add-on is considered great and beneficial.
Cons
    Recent reviews
    by Nikko Suarez, 2025-05-17
    nnnn
    by Firefox user 18986969, 2025-05-13
    by 天灭中共退党团队保平安, 2025-03-28
    View all user reviews ›

    Extension safety

    Risk impact

    MetaMask Legacy Web3 requires a few sensitive permissions. Exercise caution before installing.

    Risk impact analysis details
    • Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
    • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
    Risk likelihood

    MetaMask Legacy Web3 has earned a fairly good reputation and likely can be trusted.

    Risk likelihood analysis details
    • High This extension has low user count. Unpopular extensions may not be stable or safe.
    • Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
    • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
    • Good **** ********* *** **** **** *******
    Upgrade to see full risk analysis details

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