Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.
Auto Tab Discard - Auto Tab Discard a lightweight extension that uses the native method (tabs.
Boostnote - Boostnote is an open-source note-taking app.
Firemin - Firemin will force Firefox to use less memory. It is safe to use, spyware free and completely free.
Standard Notes - A safe place for your notes, thoughts, and life's work
BrightExplorer - Add a tabbed interface to Windows Explorer.