A browser extension with broad permissions can see every page you visit, read what you type into forms, and in some cases modify what a page displays — capabilities most people would think twice about granting to a standalone app, but click "add to browser" for without a second thought.
The specific risk that's easy to miss
Most extensions start out legitimate. The risk that catches people off guard isn't usually the initial install — it's ownership changing hands later. Small extensions get bought and sold, sometimes specifically because a large install base is valuable to whoever buys it, and a new owner can push an updated version with expanded data collection or injected ads without most users noticing the extension changed hands at all.
A practical approach
The takeaway
Extensions are convenient specifically because they operate with broad access across everything you browse — which is exactly why they deserve the same periodic review as any other standing grant of access. A quarterly look through your installed list, removing anything unused, closes most of this risk with very little effort.
