Allow CORS: Access-Control-Allow-Origin
By: Muyor
Easily add (Access-Control-Allow-Origin: *) rule to the response header.
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Features & Capabilities
User Growth & Download Statistics
- By:
- Muyor
- Daily users:
- 9,182 -56
- Rating:
- 2.69 (95)
1 new ratings - Version:
- 0.2.2 Last updated: 2026-04-23
- Version code:
- 6220031
- Creation date:
- 2018-04-25
- Risk:
- Moderate risk impact High risk likelihood
- Permissions:
- Host permissions:
- <all_urls>
- <all_urls>
- Size:
- 92.80KB
- Email:
- mu*****@gmail.com
- URLs:
- Website
- Full description:
- See detailed description
- Source:
- Firefox Add-ons Store
- Data ingested on:
- 2026-06-03
- Compare stats and ranking:
- Allow CORS: Access-Control-Allow-Origin vs CORS Unblock
- Allow CORS: Access-Control-Allow-Origin vs CORS Everywhere
- Allow CORS: Access-Control-Allow-Origin vs CORS Unblock
Contact the developer
Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Permission Change History
2024-11-04: Version 0.1.7 → 0.2.0
Add Host permissions: <all_urls>
Add Permissions: declarativeNetRequest
Remove Permissions: activeTab <all_urls> webRequestBlocking
User Reviews
Most reviews describe the add-on as a resource hog. The top issues are constant or near-100% CPU use, rapid memory growth and leaks, and battery drain/heat. Users also report background activity continuing even when disabled and, in some cases, security concerns about malware. A few note it works despite a CPU bug, but overall sentiment is negative with little to no clear pros. Pros
Cons
- Extreme CPU usage: reviewers report near-100% CPU consistently
- Memory leaks and excessive RAM consumption, sometimes reaching several GBs
- Significant battery drain and laptop overheating
- Persistent background activity and high resource use even when tabs are idle or the extension is off
- Security concerns and malware suspicions from some users
Recent reviews
Usable on some webs.
Problem is memory leak.
by Fi*****, 2026-05-30
Huge memory leaks leading to unusable Firefox....
by Tr*****, 2026-04-27
using 1 CPU core at 100% constantly. Something's wrong
by Fi*****, 2026-02-23
Is Allow CORS: Access-Control-Allow-Origin Safe?
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.
Allow CORS: Access-Control-Allow-Origin 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
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 Add-ons Store, 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.
Allow CORS: Access-Control-Allow-Origin may not be trust-worthy. Avoid installing if possible unless you really trust this publisher.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
- Medium **** ********* *** ******* ** *** **** * ******* *** ******* *** *** ** ****** ** *****
- Medium **** ********* *** *** **** *******
- Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
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