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@@ -1,2 +1,55 @@
-# vim-vixen
-Vim vixen
+# Vim Vixen
+
+An Firefox add-ons works with WebExtensions, insipired by [Vimperator](https://github.com/vimperator).
+
+## Background
+
+### Firefox will stop supporting legacy add-ons
+
+Firefox will support only add-ons using WebExtensions API since version 57, and
+plugins based on legacy APIs will be unavailable.  Vim Vixen is new solution to
+create Vim-like Firefox.
+
+### Vimimum
+
+[Vimium](https://github.com/philc/vimium) is a Chrome extension which able to
+navigate pages in Google Chrome/Chromium.  Vimium also started to suppprt on
+Firefox by WebExtensions API.
+
+## TODO
+
+- [ ] open command
+  - [x] open a link
+  - [ ] search by keywords with engined
+  - [ ] complete URLs from history
+  - [ ] complete keywords for search
+- [x] tabs navigation
+  - [x] select a tabs by keyboard
+  - [x] close/reopen a tab
+  - [x] reload a page
+- [ ] buffer control
+  - [x] select a tab by :buffer command
+  - [x] buffer completion
+  - [ ] list buffers
+  - [ ] select buffer last selected
+- [ ] discover a content
+  - [x] scroll a page by keyboard
+  - [x] zoom-in/zoom-out
+  - [ ] find a keyword in the page
+- [ ] navigations
+  - [ ] yank/paste page
+  - [ ] pagenation
+  - [ ] open parent page
+- [ ] hints
+  - [x] open a link
+  - [ ] open a link in new tab
+  - [ ] activate input form
+- [ ] misc
+  - [ ] configurable keymaps
+  - [ ] .rc file
+  - [ ] other commands in Ex mode
+- [ ] supporting Google Chrome/Chromium
+
+## Licence
+
+MIT