In short, some are and some are not. The extension’s author determines
whether the extension is free or paid, chooses the licensing model, and
sets the price.
A number of extension licensing models are available:
-
Free. Just as it says, the extension is free. Anyone can use all
of its features without paying. -
Freemium. This means that some features of the extension can be
used for free, and some can only be used after purchasing a license.
For example, a freemium extension may scan the server for
vulnerabilities when unlicensed, and automatically fix them when
licensed. -
Single offer. A paid license is required to operate the
extension. The price of the license is always the same. -
Multiple offers. A paid license is required to operate the
extension. A number of tiered licenses are available at various price
points. For example, licenses that allow you to use the extension
with 10, 50, or an unlimited number of domains may be available. -
Pay-as-you-go. Under this licensing model, you pay for the amount
of resources you consume instead of paying a set fee. -
Individual offers. Under this licensing model, website owners
purchase products and services by themselves, as needed. The
extension itself does not need a paid license to operate.