PouchDB is a 99% JavaScript database inspired by CouchDB. It enables applications to store data locally while offline, then synchronize it with CouchDB when the application is back online, keeping the user's data in sync.
Focuses on query execution speed, supports both relational as well as schemaless data, works in Node.js, mobile apps as well as in the browser. Data can also be imported from Excel, IndexedDB, Localstorage, JSON, etc.
Can be in-memory, or persistent and runs in Node, Electron, and on the browser. If you're looking for a frontend alternative to MongoDB, this is the one!
SQLite3 ported to the browser using #WebAssembly. sql.js allows you to build a fully relational database right in the client's browser, and this has a lot of potential.
Dexie.js is a wrapper for IndexedDB that can support data syncing into the cloud. It reduces browser incompatibilities and provides near-native performance.
Superfast in-memory JavaScript document-oriented database. Along with running in Node and browsers, LokiJS also runs in @NativeScript. Support for indexing and data persistence are also available.
An extension that renders Markdown files as GitHub does. Extremely useful when writing readme files, licenses, and other documentation for your project on @GitHub. Other than that, the extension also has multiple themes.
What Font is an extension that tells you what fonts a web page is being used. Clicking on some text reveals extended information like text color, font-weight, font-variant, along with sample characters in that font.