What are Crypto Wallet browser extensions?

Could you elaborate on Crypto Wallet browser extensions, please? Are these tools designed to enable seamless cryptocurrency transactions directly within a web browser? How do they function in terms of security and privacy? Are there any specific advantages or disadvantages to using such extensions compared to traditional crypto wallets? Additionally, which popular web browsers support crypto wallet extensions, and are there any steps I should take to ensure I'm using a safe and reliable extension? I'm curious to understand the overall concept and its practical applications in the cryptocurrency world.