- By:
- 1&1 Mail & Media GmbH
- Daily users:
- 1,224 -10
- Rating:
- 2.79 (76)
- Version:
- 6.5.5 Last updated: 2023-11-20
- Version code:
- 5653054
- Creation date:
- 2012-12-03
- Risk:
- Very high risk impact Moderate risk likelihood
- Permissions:
- activeTab
- tabs
- storage
- management
- notifications
- contextMenus
- identity
- search
- https://*.mail.com/*
- activeTab
- Size:
- 2.32MB
- URLs:
- Website ,Privacy policy
- Full description:
- See detailed description
- Source:
- Firefox Browser Add-ons
- Data ingested on:
- 2025-07-09
Ranking
User reviews
Pros
- Saves time by allowing quick checking of mail accounts without missing emails.
- Convenient way to view emails from multiple accounts.
- Worked well on other browsers like Chrome and Brave before issues arose.
Cons
- Currently does not work properly on Firefox; users cannot log in or get stuck on the login screen.
- Login process is broken—inputting email disables the login button and never prompts for password.
- Requires excessive permissions, raising privacy and security concerns.
- Extension compatibility with latest Firefox versions is problematic, with no recent updates.
- Extension freezes or hangs after installation on Firefox.
Recent reviews
by 天灭*****, 2025-02-13
by Fi*****, 2024-12-21
Not working, simple as that.
by se*****, 2024-11-26
Extension safety
Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk
impact extension cannot do much harms, whereas a high risk impact extension can do a lot of
damage like stealing your password, bypassing your security settings, and accessing your
personal data. High risk impact extensions are not necessarily malicious. However, if they
do turn malicious, they can be very harmful.
mail.com MailCheck requires a lot of sensitive permissions. Exercise caution before installing.
Risk impact analysis details
- Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
- Critical ******* ****** ** *** ********* ******** ********************
- High *** ****** ****** ********** ***** ***** ******** ******** ** ********* ****** ****** ******** *****
- High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
- Medium ******* ***** *********** ***** ****** ********* *** ***** ********* **** **** ************** *** ********
- Medium ******* ******* ************* ***** *** ** ******* *** **** ******* ****** ******** *******
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious.
This is determined by the publisher and the Firefox add-on reputation on
Firefox Browser Add-ons, the amount of time the Firefox add-on has been
around, and other signals about the
Firefox add-on. Our algorithms are not perfect, and are subject to change
as we discover new ways to detect malicious extensions. We recommend that you always
exercise caution when installing a Firefox add-on.
mail.com MailCheck is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
- Medium **** ********* *** *** **** *******
- Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
- Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Upgrade to see full risk analysis details
Compare add-ons
- Compare mail.com MailCheck vs WEB.DE MailCheck for Firefox
- Compare mail.com MailCheck vs GMX MailCheck for Firefox
- Compare mail.com MailCheck vs Email Notifier
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