diff --git a/.circleci/config.yml b/.circleci/config.yml
index 2d83bc3..3a2bae4 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -70,6 +70,7 @@ jobs:
     executor:
       name: default
     steps:
+      - run: sudo apt-get update && sudo apt-get -y install xsel
       - install_firefox
       - checkout
       - setup_npm
diff --git a/QA.md b/QA.md
index 4d1a270..16b4442 100644
--- a/QA.md
+++ b/QA.md
@@ -10,17 +10,13 @@ The behaviors of the console are tested in [Console section](#consoles).
 
 #### Misc
 
-- [ ] <kbd>y</kbd>: yank current URL and show a message
-- [ ] <kbd>p</kbd>: open clipboard's URL in current tab
-- [ ] <kbd>P</kbd>: open clipboard's URL in new tab
-- [ ] <kbd>p</kbd>: search clipboard's keywords in current tab
-- [ ] <kbd>P</kbd>: search clipboard's keywords in new tab
 - [ ] Toggle enabled/disabled of plugin bu <kbd>Shift</kbd>+<kbd>Esc</kbd>
 - [ ] Hide error and info console by <kbd>Esc</kbd>
 - [ ] Vim-Vixen icons changes on <kbd>Shift</kbd>+<kbd>Esc</kbd>
 - [ ] Add-on is enabled and disabled by clicking the indicator on the tool bar.
 - [ ] The indicator changed on selected tab changed (changes add-on enabled)
 - [ ] Notify to users on add-on updated at first time.
+- [ ] Reopen tab on *only current window* by <kbd>u</kbd>
 
 ### Following links
 
@@ -31,6 +27,7 @@ The behaviors of the console are tested in [Console section](#consoles).
 - [ ] Select link and open it in new tab in `<iframe>`/`<frame`> on following by <kbd>F</kbd>
 - [ ] Select link and open it in `<area>` tags, for <kbd>f</kbd> and <kbd>F</kbd>
 - [ ] Open new tab in background by `"background": true`
+- [ ] Opened tabs is in child on Tree Style Tab
 
 ### Consoles
 
@@ -38,40 +35,14 @@ The behaviors of the console are tested in [Console section](#consoles).
 
 - [ ] `<EMPTY>`: do nothing
 
-### Completions
-
-#### History and search engines
-
-- [ ] `open<SP>`: show all engines and some history items
-- [ ] `open g`: complete search engines starts with `g` and matched with keywords `g`
-- [ ] `open foo bar`: complete history items matched with keywords `foo` and `bar`
-- [ ] `set `: show prperties starts with keywords
-- [ ] The completions shows histories, search engines, and bookmarks.
-- [ ] also `tabopen` and `winopen`
-- shortening commands such as `o` are not test in this release
-- [ ] Complete commands matched with input keywords in the prefix.
-
-#### Buffer command
-
-- [ ] `buffer<SP>`: show all opened tabs in completion
-- [ ] `buffer x`: show tabs which has title and URL matches with `x`
-- [ ] shows tab index and marks
-
-#### Buffer command
-
-- [ ] `bdelete`, `bdeletes`: show tabs excluding pinned tabs
-- [ ] `bdelete!`, `bdeletes!`: show tabs including pinned tabs
-
 #### Misc
 
 - [ ] Select next item by <kbd>Tab</kbd> and previous item by <kbd>Shift</kbd>+<kbd>Tab</kbd>
-- [ ] Reopen tab on *only current window* by <kbd>u</kbd>
 
 ### Properties
 
 - [ ] Configure custom hint character by `:set hintchars=012345678`
 - [ ] Configure custom hint character by settings `"hintchars": "012345678"` in add-on preferences
-- [ ] Opened tabs is in child on Tree Style Tab
 
 - [ ] Smooth scroll by `:set smoothscroll`
 - [ ] Non-smooth scroll by `:set nosmoothscroll`
diff --git a/e2e/clipboard.test.js b/e2e/clipboard.test.js
new file mode 100644
index 0000000..82e45fc
--- /dev/null
+++ b/e2e/clipboard.test.js
@@ -0,0 +1,123 @@
+const express = require('express');
+const lanthan = require('lanthan');
+const path = require('path');
+const assert = require('assert');
+const eventually = require('./eventually');
+const clipboard = require('./lib/clipboard');
+const settings = require('./settings');
+
+const Key = lanthan.Key;
+
+const newApp = () => {
+  let app = express();
+  app.get('/', (req, res) => {
+    res.status(200).send(`<html lang="en"></html">`);
+  });
+  return app;
+};
+
+describe("navigate test", () => {
+
+  const port = 12321;
+  let http;
+  let firefox;
+  let session;
+  let browser;
+
+  before(async() => {
+    http = newApp().listen(port);
+
+    firefox = await lanthan.firefox({
+      spy: path.join(__dirname, '..'),
+    });
+    session = firefox.session;
+    browser = firefox.browser;
+
+    await browser.storage.local.set({
+      settings,
+    });
+  });
+
+  after(async() => {
+    if (firefox) {
+      await firefox.close();
+    }
+    http.close();
+  });
+
+  beforeEach(async() => {
+    let tabs = await browser.tabs.query({});
+    for (let tab of tabs.slice(1)) {
+      await browser.tabs.remove(tab.id);
+    }
+  })
+
+  it('should copy current URL by y', async () => {
+    await session.navigateTo(`http://127.0.0.1:${port}/#should_copy_url`);
+    let body = await session.findElementByCSS('body');
+
+    await body.sendKeys('y');
+    await eventually(async() => {
+      let data = await clipboard.read();
+      assert.equal(data, `http://127.0.0.1:${port}/#should_copy_url`);
+    });
+  });
+
+  it('should open an URL from clipboard by p', async () => {
+    await session.navigateTo(`http://127.0.0.1:${port}/`);
+    let body = await session.findElementByCSS('body');
+
+    await clipboard.write(`http://127.0.0.1:${port}/#open_from_clipboard`);
+    await body.sendKeys('p');
+
+    await eventually(async() => {
+      let tabs = await browser.tabs.query({ active: true });
+      assert.equal(tabs[0].url, `http://127.0.0.1:${port}/#open_from_clipboard`);
+    });
+  });
+
+  it('should open an URL from clipboard to new tab by P', async () => {
+    await session.navigateTo(`http://127.0.0.1:${port}/`);
+    let body = await session.findElementByCSS('body');
+
+    await clipboard.write(`http://127.0.0.1:${port}/#open_to_new_tab`);
+    await body.sendKeys(Key.Shift, 'p');
+
+    await eventually(async() => {
+      let tabs = await browser.tabs.query({});
+      assert.deepEqual(tabs.map(t => t.url), [
+        `http://127.0.0.1:${port}/`,
+        `http://127.0.0.1:${port}/#open_to_new_tab`,
+      ]);
+    });
+  });
+
+  it('should open search result with keywords in clipboard by p', async () => {
+    await session.navigateTo(`http://127.0.0.1:${port}/`);
+    let body = await session.findElementByCSS('body');
+
+    await clipboard.write(`an apple`);
+    await body.sendKeys('p');
+
+    await eventually(async() => {
+      let tabs = await browser.tabs.query({});
+      assert.equal(tabs[0].url, `http://127.0.0.1:${port}/google?q=an%20apple`);
+    });
+  });
+
+  it('should open search result with keywords in clipboard to new tabby P', async () => {
+    await session.navigateTo(`http://127.0.0.1:${port}/`);
+    let body = await session.findElementByCSS('body');
+
+    await clipboard.write(`an apple`);
+    await body.sendKeys(Key.Shift, 'p');
+
+    await eventually(async() => {
+      let tabs = await browser.tabs.query({});
+      assert.deepEqual(tabs.map(t => t.url), [
+        `http://127.0.0.1:${port}/`,
+        `http://127.0.0.1:${port}/google?q=an%20apple`,
+      ]);
+    });
+  });
+});
diff --git a/e2e/completion.test.js b/e2e/completion.test.js
new file mode 100644
index 0000000..5d910c6
--- /dev/null
+++ b/e2e/completion.test.js
@@ -0,0 +1,136 @@
+const express = require('express');
+const lanthan = require('lanthan');
+const path = require('path');
+const assert = require('assert');
+const eventually = require('./eventually');
+const settings = require('./settings');
+const Console = require('./lib/Console');
+
+const Key = lanthan.Key;
+
+const newApp = () => {
+  let app = express();
+  app.get('/', (req, res) => {
+    res.send(`<!DOCTYPEhtml>
+<html lang="en">
+  <body>ok</body>
+</html">`);
+  });
+  return app;
+};
+
+describe("general completion test", () => {
+  const port = 12321;
+  let http;
+  let firefox;
+  let session;
+  let browser;
+  let body;
+
+  before(async() => {
+    firefox = await lanthan.firefox({
+      spy: path.join(__dirname, '..'),
+      builderf: (builder) => {
+        builder.addFile('build/settings.js');
+      },
+    });
+    session = firefox.session;
+    browser = firefox.browser;
+    http = newApp().listen(port);
+
+    await browser.storage.local.set({
+      settings,
+    });
+  });
+
+  after(async() => {
+    http.close();
+    if (firefox) {
+      await firefox.close();
+    }
+  });
+
+  beforeEach(async() => {
+    await session.navigateTo(`http://127.0.0.1:${port}`);
+    body = await session.findElementByCSS('body');
+  });
+
+  it('should all commands on empty line', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 10);
+      assert.deepEqual(items[0], { type: 'title', text: 'Console Command' });
+      assert(items[1].text.startsWith('set'))
+      assert(items[2].text.startsWith('open'))
+      assert(items[3].text.startsWith('tabopen'))
+    });
+  });
+
+  it('should only commands filtered by prefix', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('b');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 4);
+      assert.deepEqual(items[0], { type: 'title', text: 'Console Command' });
+      assert(items[1].text.startsWith('buffer'))
+      assert(items[2].text.startsWith('bdelete'))
+      assert(items[3].text.startsWith('bdeletes'))
+    });
+  });
+
+  it('selects completion items by <Tab>/<S-Tab> keys', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('b');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 4);
+    });
+
+    await c.sendKeys(Key.Tab);
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert(items[1].highlight)
+
+      let v = await c.currentValue();
+      assert.equal(v, 'buffer');
+    });
+
+    await c.sendKeys(Key.Tab, Key.Tab);
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert(items[3].highlight)
+
+      let v = await c.currentValue();
+      assert.equal(v, 'bdeletes');
+    });
+
+    await c.sendKeys(Key.Tab);
+    await eventually(async() => {
+      let v = await c.currentValue();
+      assert.equal(v, 'b');
+    });
+
+    await c.sendKeys(Key.Shift, Key.Tab);
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert(items[3].highlight)
+
+      let v = await c.currentValue();
+      assert.equal(v, 'bdeletes');
+    });
+  });
+});
diff --git a/e2e/completion_buffers.test.js b/e2e/completion_buffers.test.js
new file mode 100644
index 0000000..de26747
--- /dev/null
+++ b/e2e/completion_buffers.test.js
@@ -0,0 +1,214 @@
+const express = require('express');
+const lanthan = require('lanthan');
+const path = require('path');
+const assert = require('assert');
+const eventually = require('./eventually');
+const settings = require('./settings');
+const Console = require('./lib/Console');
+
+const Key = lanthan.Key;
+
+const newApp = () => {
+
+  let app = express();
+  app.get('/*', (req, res) => {
+    res.send(`<!DOCTYPEhtml>
+<html lang="en">
+  <head>
+    <title>title_${req.path.slice(1)}</title>
+  </head>
+  <body><h1>home</h1></body>
+</html">`);
+  });
+  return app;
+};
+
+describe("completion on buffer/bdelete/bdeletes", () => {
+  const port = 12321;
+  let http;
+  let firefox;
+  let session;
+  let browser;
+  let body;
+
+  before(async() => {
+    firefox = await lanthan.firefox({
+      spy: path.join(__dirname, '..'),
+      builderf: (builder) => {
+        builder.addFile('build/settings.js');
+      },
+    });
+    session = firefox.session;
+    browser = firefox.browser;
+    http = newApp().listen(port);
+
+    await browser.storage.local.set({
+      settings,
+    });
+  });
+
+  after(async() => {
+    http.close();
+    if (firefox) {
+      await firefox.close();
+    }
+  });
+
+  beforeEach(async() => {
+    let tabs = await browser.tabs.query({});
+    for (let tab of tabs.slice(1)) {
+      await browser.tabs.remove(tab.id);
+    }
+
+    await browser.tabs.update(tabs[0].id, { url: `http://127.0.0.1:${port}/site1`, pinned: true });
+    await browser.tabs.create({ url: `http://127.0.0.1:${port}/site2`, pinned: true })
+    for (let i = 3; i <= 5; ++i) {
+      await browser.tabs.create({ url: `http://127.0.0.1:${port}/site${i}` })
+    }
+
+    await eventually(async() => {
+      let handles = await session.getWindowHandles();
+      assert.equal(handles.length, 5);
+      await session.switchToWindow(handles[2]);
+      await session.findElementByCSS('iframe');
+    });
+    body = await session.findElementByCSS('body');
+
+    await new Promise((resolve) => setTimeout(resolve, 100));
+  });
+
+  it('should all tabs by "buffer" command with empty params', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('buffer ');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 6);
+      assert.deepEqual(items[0], { type: 'title', text: 'Buffers' });
+      assert(items[1].text.startsWith('1:'));
+      assert(items[2].text.startsWith('2:'));
+      assert(items[3].text.startsWith('3:'));
+      assert(items[4].text.startsWith('4:'));
+      assert(items[5].text.startsWith('5:'));
+
+      assert(items[3].text.includes('%'));
+      assert(items[5].text.includes('#'));
+    });
+  })
+
+  it('should filter items with URLs by keywords on "buffer" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('buffer title_site2');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.deepEqual(items[0], { type: 'title', text: 'Buffers' });
+      assert(items[1].text.startsWith('2:'));
+      assert(items[1].text.includes('title_site2'));
+      assert(items[1].text.includes(`http://127.0.0.1:${port}/site2`));
+    });
+  })
+
+  it('should filter items with titles by keywords on "buffer" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('buffer /site2');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.deepEqual(items[0], { type: 'title', text: 'Buffers' });
+      assert(items[1].text.startsWith('2:'));
+    });
+  })
+
+  it('should show one item by number on "buffer" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('buffer 2');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 2);
+      assert.deepEqual(items[0], { type: 'title', text: 'Buffers' });
+      assert(items[1].text.startsWith('2:'));
+    });
+  })
+
+  it('should show unpinned tabs "bdelete" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('bdelete site');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 4);
+      assert(items[1].text.includes('site3'));
+      assert(items[2].text.includes('site4'));
+      assert(items[3].text.includes('site5'));
+    });
+  })
+
+  it('should show unpinned tabs "bdeletes" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('bdelete site');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 4);
+      assert(items[1].text.includes('site3'));
+      assert(items[2].text.includes('site4'));
+      assert(items[3].text.includes('site5'));
+    });
+  })
+
+  it('should show both pinned and unpinned tabs "bdelete!" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('bdelete! site');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 6);
+      assert(items[1].text.includes('site1'));
+      assert(items[2].text.includes('site2'));
+      assert(items[3].text.includes('site3'));
+      assert(items[4].text.includes('site4'));
+      assert(items[5].text.includes('site5'));
+    });
+  })
+
+  it('should show both pinned and unpinned tabs "bdeletes!" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('bdeletes! site');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 6);
+      assert(items[1].text.includes('site1'));
+      assert(items[2].text.includes('site2'));
+      assert(items[3].text.includes('site3'));
+      assert(items[4].text.includes('site4'));
+      assert(items[5].text.includes('site5'));
+    });
+  })
+});
diff --git a/e2e/completion_open.test.js b/e2e/completion_open.test.js
new file mode 100644
index 0000000..59d6b83
--- /dev/null
+++ b/e2e/completion_open.test.js
@@ -0,0 +1,132 @@
+const express = require('express');
+const lanthan = require('lanthan');
+const path = require('path');
+const assert = require('assert');
+const eventually = require('./eventually');
+const settings = require('./settings');
+const Console = require('./lib/Console');
+
+const Key = lanthan.Key;
+
+const newApp = () => {
+
+  let app = express();
+  app.get('/', (req, res) => {
+    res.send(`<!DOCTYPEhtml>
+<html lang="en">
+  <body>ok</body>
+</html">`);
+  });
+  return app;
+};
+
+describe("completion on open/tabopen/winopen commands", () => {
+  const port = 12321;
+  let http;
+  let firefox;
+  let session;
+  let browser;
+  let body;
+
+  before(async() => {
+    firefox = await lanthan.firefox({
+      spy: path.join(__dirname, '..'),
+      builderf: (builder) => {
+        builder.addFile('build/settings.js');
+      },
+    });
+    session = firefox.session;
+    browser = firefox.browser;
+    http = newApp().listen(port);
+
+    await browser.storage.local.set({
+      settings,
+    });
+    
+    // Add item into hitories
+    await session.navigateTo(`https://i-beam.org`);
+  });
+
+  after(async() => {
+    http.close();
+    if (firefox) {
+      await firefox.close();
+    }
+  });
+
+  beforeEach(async() => {
+    await session.navigateTo(`http://127.0.0.1:${port}`);
+    body = await session.findElementByCSS('body');
+  });
+
+  it('should show completions from search engines, bookmarks, and histories by "open" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('open ');
+
+    await eventually(async() => {
+      let completions = await c.getCompletions();
+      assert(completions.find(x => x.type === 'title' && x.text === 'Search Engines'));
+      assert(completions.find(x => x.type === 'title' && x.text === 'Bookmarks'));
+      assert(completions.find(x => x.type === 'title' && x.text === 'History'));
+    });
+  });
+
+  it('should filter items with URLs by keywords on "open" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('open https://');
+
+    await eventually(async() => {
+      let completions = await c.getCompletions();
+      let items = completions.filter(x => x.type === 'item').map(x => x.text);
+      assert(items.every(x => x.includes('https://')));
+    });
+  })
+
+  it('should filter items with titles by keywords on "open" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('open getting');
+
+    await eventually(async() => {
+      let completions = await c.getCompletions();
+      let items = completions.filter(x => x.type === 'item').map(x => x.text);
+      assert(items.every(x => x.toLowerCase().includes('getting')));
+    });
+  })
+
+  it('should filter items with titles by keywords on "tabopen" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('tabopen https://');
+
+    await eventually(async() => {
+      let completions = await c.getCompletions();
+      let items = completions.filter(x => x.type === 'item').map(x => x.text);
+      assert(items.every(x => x.includes('https://')));
+    });
+  })
+
+  it('should filter items with titles by keywords on "winopen" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('winopen https://');
+
+    await eventually(async() => {
+      let completions = await c.getCompletions();
+      let items = completions.filter(x => x.type === 'item').map(x => x.text);
+      assert(items.every(x => x.includes('https://')));
+    });
+  })
+});
diff --git a/e2e/completion_set.test.js b/e2e/completion_set.test.js
new file mode 100644
index 0000000..cf5ff5b
--- /dev/null
+++ b/e2e/completion_set.test.js
@@ -0,0 +1,75 @@
+const express = require('express');
+const lanthan = require('lanthan');
+const path = require('path');
+const assert = require('assert');
+const eventually = require('./eventually');
+const settings = require('./settings');
+const Console = require('./lib/Console');
+
+const Key = lanthan.Key;
+
+describe("completion on set commands", () => {
+  const port = 12321;
+  let firefox;
+  let session;
+  let browser;
+  let body;
+
+  before(async() => {
+    firefox = await lanthan.firefox({
+      spy: path.join(__dirname, '..'),
+      builderf: (builder) => {
+        builder.addFile('build/settings.js');
+      },
+    });
+    session = firefox.session;
+    browser = firefox.browser;
+
+    await browser.storage.local.set({
+      settings,
+    });
+  });
+
+  after(async() => {
+    if (firefox) {
+      await firefox.close();
+    }
+  });
+
+  beforeEach(async() => {
+    await session.navigateTo(`about:blank`);
+    body = await session.findElementByCSS('body');
+  });
+
+  it('should show all property names by "set" command with empty params', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('set ');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 5);
+      assert.deepEqual(items[0], { type: 'title', text: 'Properties' });
+      assert(items[1].text.startsWith('hintchars'))
+      assert(items[2].text.startsWith('smoothscroll'))
+      assert(items[3].text.startsWith('nosmoothscroll'))
+      assert(items[4].text.startsWith('complete'))
+    });
+  });
+
+  it('should show filtered property names by "set" command', async() => {
+    await body.sendKeys(':');
+
+    await session.switchToFrame(0);
+    let c = new Console(session);
+    await c.sendKeys('set no');
+
+    await eventually(async() => {
+      let items = await c.getCompletions();
+      assert.equal(items.length, 2);
+      assert(items[1].text.includes('nosmoothscroll'))
+    });
+  });
+});
diff --git a/e2e/lib/Console.js b/e2e/lib/Console.js
new file mode 100644
index 0000000..3a39b64
--- /dev/null
+++ b/e2e/lib/Console.js
@@ -0,0 +1,41 @@
+class Console {
+  constructor(session) {
+    this.session = session;
+  }
+
+  async sendKeys(...keys) {
+    let input = await this.session.findElementByCSS('input');
+    input.sendKeys(...keys);
+  }
+
+  async currentValue() {
+    return await this.session.executeScript(() => {
+      let input = document.querySelector('input');
+      return input.value;
+    });
+  }
+
+  async getCompletions() {
+    return await this.session.executeScript(() => {
+      let items = document.querySelectorAll('.vimvixen-console-completion > li');
+      if (items.length === 0) {
+        throw new Error('completion items not found');
+      }
+
+      let objs = [];
+      for (let li of items) {
+        if (li.classList.contains('vimvixen-console-completion-title')) {
+          objs.push({ type: 'title', text: li.textContent.trim() });
+        } else if ('vimvixen-console-completion-item') {
+          let highlight = li.classList.contains('vimvixen-completion-selected');
+          objs.push({ type: 'item', text: li.textContent.trim(), highlight });
+        } else {
+          throw new Error(`unexpected class: ${li.className}`);
+        }
+      }
+      return objs;
+    });
+  }
+}
+
+module.exports = Console;
diff --git a/e2e/lib/clipboard.js b/e2e/lib/clipboard.js
new file mode 100644
index 0000000..4061dbd
--- /dev/null
+++ b/e2e/lib/clipboard.js
@@ -0,0 +1,63 @@
+'use strict';
+
+const { spawn } = require('child_process');
+
+const readLinux = () => {
+  let stdout = '', stderr = '';
+  return new Promise((resolve, reject) => {
+    let xsel = spawn('xsel', ['--clipboard', '--output']);
+    xsel.stdout.on('data', (data) => {
+      stdout += data;
+    });
+    xsel.stderr.on('data', (data) => {
+      stderr += data;
+    });
+    xsel.on('close', (code) => {
+      if (code !== 0) {
+        throw new Error(`xsel returns ${code}: ${stderr}`)
+      }
+      resolve(stdout);
+    });
+  });
+};
+
+const writeLinux = (data) => {
+  let stdout = '', stderr = '';
+  return new Promise((resolve, reject) => {
+    let xsel = spawn('xsel', ['--clipboard', '--input']);
+    xsel.stderr.on('data', (data) => {
+      stderr += data;
+    });
+    xsel.on('close', (code) => {
+      if (code !== 0) {
+        throw new Error(`xsel returns ${code}: ${stderr}`)
+      }
+      resolve();
+    });
+    xsel.stdin.write(data);
+    xsel.stdin.end();
+  });
+};
+
+const unsupported = (os) => {
+  return () => {
+    throw new Error(`Unsupported os: ${os}`);
+  };
+};
+
+const detect = () => {
+  switch (process.platform) {
+    case 'linux':
+      return {
+        read: readLinux,
+        write: writeLinux,
+      };
+    default:
+      return {
+        read: unsupported(process.platform),
+        write: unsupported(process.platform),
+      };
+  }
+}
+
+module.exports = detect();
diff --git a/package-lock.json b/package-lock.json
index df179de..53eb21d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -6854,7 +6854,7 @@
       }
     },
     "lanthan": {
-      "version": "git+https://github.com/ueokande/lanthan.git#2a2aa2ebfc1ce8528fae8b01992ae56967e18f8a",
+      "version": "git+https://github.com/ueokande/lanthan.git#a6795eb90006b11e65d436becda339258c00643c",
       "from": "git+https://github.com/ueokande/lanthan.git#master",
       "dev": true,
       "requires": {
