Greasemonkey

Name: Greasemonkey
Rating: 4.1775 (1262 reviews)
Author: Anthony Lieuallen

Customize the way a web page displays or behaves, by using small bits of JavaScript.

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Greasemonkey is a powerful Chrome extension that enables users to customize the appearance and behavior of web pages through small JavaScript scripts. Whether you want to modify layouts, add new functionalities, or automate repetitive tasks, Greasemonkey provides a flexible platform to personalize your browsing experience.

Users can create their own scripts or utilize a vast collection of existing ones available on the Greasemonkey wiki. This extension empowers you to enhance your favorite websites to better suit your needs without requiring advanced development skills. For support and tutorials, the Greasemonkey manual and script hosting resources are a great starting point.

Developer Tools Productivity Programming Utilities

By:

Daily users:

Rating:

Version:

4.13 Last updated: 2024-08-07

Version code:

5787800

Creation date:

2005-05-20

Risk:

Permissions:

<all_urls>
clipboardWrite
cookies
downloads
notifications
storage
tabs
unlimitedStorage
webNavigation
webRequest

Size:

630.49K

URLs:

Website

Full description:

Source:

Firefox Browser Add-ons

Updated:

a day ago

Ranking

# 103 ▼ 2

Other rankings

#25 in Other extensions

#2 in reason keyword 2

#13 in money keyword 27 ▼ 1

#28 in keyword keyword 62

#30 in base keyword 10

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User reviews

User reviews of the Greasemonkey Firefox add-on are mixed. Some users find it perfect and highly effective, while others report that it does not work for them and criticize the lack of support and outdated tutorials. The main positive points revolve around its flawless performance for certain users, whereas the top negatives highlight functionality issues and insufficient support resources.

Pros

Works perfectly for some users
Highly appreciated by certain users

Cons

Not working for some users
Lack of support and outdated or mismatched tutorials

Recent reviews

by Alch, 2025-04-26

by Firefox user 15264794, 2025-04-20

by 全民三退解体中共邪教, 2025-03-27

View all user reviews ›

Extension safety

Risk impact

Greasemonkey requires a lot of 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.
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Medium ****** ********** ** ******** ********** *** ********* ******* ******** ****** ******** ****** ********
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Risk likelihood

Greasemonkey has earned a fairly good reputation and likely can be trusted.

Risk likelihood analysis details

Low This extension was updated more than 6 months ago. Older versions are more likely to be stable and safe.
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