A browser extension is a small application that adds a capacity or functionality to a browser. Browser extensions are coded for specific browsers but most offer versions for all the most popular browsers.
Extensions can add features, enhance websites and integrate various applications and services. The add-ons can also remove unwanted website elements and features such as auto-play video, pop-up ads and overlay pop-ups that obscure the content you’re trying to access when you visit a site.
Here are a few examples of browser extensions:
- AdBlock enables content filtering and ad blocking.
- HTTPS Everywhere makes websites automatically connect through HTTPS for greater security, assuming they support it.
- F.lux changes the color of the display when the sun goes down, reducing blue light, which can interfere with the user’s sleep.
- StayFocusd limits the amount of time that users can spend on specified websites, to reduce wasted time and improve productivity.
- Sidenotes allows users to write in a notepad that opens in a panel alongside the current page.
Like other types of software, browser extensions can be coded for undesirable behaviors, in which case they are one form of malware. In January 2018, it a security company called ICEBERG reported that four malicious extensions available from the Chrome Web Store were designed to conduct click fraud and black hat SEO. In 2017, Proofpoint reported that eight compromised Chrome extensions had sent malicious code to almost four and a half million users.