 Essential extension

An extension $N\subseteq M$ is essential when $N$ is an essential submodule of $M$. Essentiality is transitive. It is an intersection condition, not a statement that the quotient is small in dimension or finitely generated.

The term "Essential extension" can refer to different concepts depending on the context, such as software development, web browsers, or various frameworks. Here are a few common interpretations: 1. **Web Browser Extensions**: In the context of web browsers, an "essential extension" typically refers to a browser add-on that significantly enhances usability, security, or productivity. Examples include ad blockers, password managers, and privacy-focused extensions.