diff --git a/qutebrowser/app.py b/qutebrowser/app.py
index 8b7e6b927..372b0b4e7 100644
--- a/qutebrowser/app.py
+++ b/qutebrowser/app.py
@@ -57,9 +57,6 @@ from qutebrowser.utils.appdirs import AppDirs
 from qutebrowser.utils.misc import set_trace
 
 
-components = {}
-
-
 class QuteBrowser(QApplication):
 
     """Main object for qutebrowser.
@@ -133,8 +130,6 @@ class QuteBrowser(QApplication):
         self.keyparser.keystring_updated.connect(
             self.mainwindow.status.keystring.setText)
 
-        components['app'] = self
-
         self.mainwindow.show()
         self._python_hacks()
         timer = QTimer.singleShot(0, self._process_init_args)
diff --git a/qutebrowser/commands/utils.py b/qutebrowser/commands/utils.py
index afde5bc1e..c6c94fad4 100644
--- a/qutebrowser/commands/utils.py
+++ b/qutebrowser/commands/utils.py
@@ -26,7 +26,6 @@ from PyQt5.QtWidgets import QApplication
 from PyQt5.QtWebKitWidgets import QWebPage
 
 import qutebrowser.config.config as config
-from qutebrowser.app import components as qtb_components
 from qutebrowser.commands.template import Command
 from qutebrowser.commands.exceptions import (ArgumentCountError,
                                              NoSuchCommandError)
@@ -64,7 +63,7 @@ class register:
         count, nargs = self._get_nargs_count(func)
         desc = func.__doc__.splitlines()[0].strip().rstrip('.')
         if self.instance is not None:
-            handler = functools.partial(func, qtb_components[self.instance])
+            handler = functools.partial(func, instance])
         else:
             handler = func
         cmd = Command(mainname, self.split_args, self.hide, nargs, count, desc,
@@ -139,7 +138,6 @@ class SearchParser(QObject):
         self._text = None
         self._flags = 0
         super().__init__(parent)
-        qtb_components['searchparser'] = self
 
     def _search(self, text, rev=False):
         """Search for a text on the current page.
diff --git a/qutebrowser/widgets/browser.py b/qutebrowser/widgets/browser.py
index af14d2bae..fa14d9faf 100644
--- a/qutebrowser/widgets/browser.py
+++ b/qutebrowser/widgets/browser.py
@@ -37,7 +37,6 @@ from PyQt5.QtWebKitWidgets import QWebView, QWebPage
 import qutebrowser.utils.url as urlutils
 import qutebrowser.config.config as config
 import qutebrowser.commands.utils as cmdutils
-from qutebrowser.app import components as qtb_components
 from qutebrowser.widgets.tabbar import TabWidget
 from qutebrowser.network.networkmanager import NetworkManager
 from qutebrowser.utils.signals import SignalCache, dbg_signal
@@ -115,7 +114,6 @@ class TabbedBrowser(TabWidget):
         self._space.activated.connect(lambda: self.cur.scroll_page(0, 1))
         self.cur = CurCommandDispatcher(self)
         self.cur.temp_message.connect(self.cur_temp_message)
-        qtb_components['browser'] = self
 
     def _cb_tab_shutdown(self, tab):
         """Called after a tab has been shut down completely.
@@ -249,7 +247,7 @@ class TabbedBrowser(TabWidget):
             tab.shutdown(callback=functools.partial(self._cb_tab_shutdown,
                                                     tab))
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs')
     def tabclose(self, count=None):
         """Close the current/[count]th tab.
 
@@ -279,7 +277,7 @@ class TabbedBrowser(TabWidget):
         elif last_close == 'blank':
             tab.openurl('about:blank')
 
-    @cmdutils.register(instance='browser', split_args=False)
+    @cmdutils.register(instance='mainwindow.tabs', split_args=False)
     def tabopen(self, url):
         """Open a new tab with a given url.
 
@@ -313,7 +311,7 @@ class TabbedBrowser(TabWidget):
         tab.open_tab.connect(self.tabopen)
         tab.openurl(url)
 
-    @cmdutils.register(instance='browser', hide=True)
+    @cmdutils.register(instance='mainwindow.tabs', hide=True)
     def tabopencur(self):
         """Set the statusbar to :tabopen and the current URL.
 
@@ -324,7 +322,7 @@ class TabbedBrowser(TabWidget):
         url = urlutils.urlstring(self.currentWidget().url())
         self.set_cmd_text.emit(':tabopen ' + url)
 
-    @cmdutils.register(instance='browser', hide=True)
+    @cmdutils.register(instance='mainwindow.tabs', hide=True)
     def opencur(self):
         """Set the statusbar to :open and the current URL.
 
@@ -335,7 +333,7 @@ class TabbedBrowser(TabWidget):
         url = urlutils.urlstring(self.currentWidget().url())
         self.set_cmd_text.emit(':open ' + url)
 
-    @cmdutils.register(instance='browser', name='undo')
+    @cmdutils.register(instance='mainwindow.tabs', name='undo')
     def undo_close(self):
         """Switch to the previous tab, or skip [count] tabs.
 
@@ -345,7 +343,7 @@ class TabbedBrowser(TabWidget):
         if self._url_stack:
             self.tabopen(self._url_stack.pop())
 
-    @cmdutils.register(instance='browser', name='tabprev')
+    @cmdutils.register(instance='mainwindow.tabs', name='tabprev')
     def switch_prev(self, count=1):
         """Switch to the ([count]th) previous tab.
 
@@ -362,7 +360,7 @@ class TabbedBrowser(TabWidget):
             # FIXME
             pass
 
-    @cmdutils.register(instance='browser', name='tabnext')
+    @cmdutils.register(instance='mainwindow.tabs', name='tabnext')
     def switch_next(self, count=1):
         """Switch to the next tab, or skip [count] tabs.
 
@@ -379,7 +377,7 @@ class TabbedBrowser(TabWidget):
             # FIXME
             pass
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs')
     def paste(self, sel=False):
         """Open a page from the clipboard.
 
@@ -396,7 +394,7 @@ class TabbedBrowser(TabWidget):
         logging.debug("Clipboard contained: '{}'".format(url))
         self.openurl(url)
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs')
     def tabpaste(self, sel=False):
         """Open a page from the clipboard in a new tab.
 
@@ -491,7 +489,8 @@ class CurCommandDispatcher(QObject):
             return
         frame.setScrollBarValue(orientation, int(m * perc / 100))
 
-    @cmdutils.register(instance='browser', name='open', split_args=False)
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='open',
+                       split_args=False)
     def openurl(self, url, count=None):
         """Open an url in the current/[count]th tab.
 
@@ -514,7 +513,7 @@ class CurCommandDispatcher(QObject):
         else:
             tab.openurl(url)
 
-    @cmdutils.register(instance='browser', name='reload')
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='reload')
     def reloadpage(self, count=None):
         """Reload the current/[count]th tab.
 
@@ -528,7 +527,7 @@ class CurCommandDispatcher(QObject):
         if tab is not None:
             tab.reload()
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs.cur')
     def stop(self, count=None):
         """Stop loading in the current/[count]th tab.
 
@@ -542,7 +541,7 @@ class CurCommandDispatcher(QObject):
         if tab is not None:
             tab.stop()
 
-    @cmdutils.register(instance='browser', name='print')
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='print')
     def printpage(self, count=None):
         """Print the current/[count]th tab.
 
@@ -559,7 +558,7 @@ class CurCommandDispatcher(QObject):
             preview.paintRequested.connect(tab.print)
             preview.exec_()
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs.cur')
     def back(self, count=1):
         """Go back in the history of the current tab.
 
@@ -573,7 +572,7 @@ class CurCommandDispatcher(QObject):
         for i in range(count):  # pylint: disable=unused-variable
             self.tabs.currentWidget().back()
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs.cur')
     def forward(self, count=1):
         """Go forward in the history of the current tab.
 
@@ -598,7 +597,7 @@ class CurCommandDispatcher(QObject):
         """
         self.tabs.currentWidget().findText(text, flags)
 
-    @cmdutils.register(instance='browser', hide=True)
+    @cmdutils.register(instance='mainwindow.tabs.cur', hide=True)
     def scroll(self, dx, dy, count=1):
         """Scroll the current tab by count * dx/dy.
 
@@ -614,7 +613,8 @@ class CurCommandDispatcher(QObject):
         dy = int(count) * float(dy)
         self.tabs.currentWidget().page_.mainFrame().scroll(dx, dy)
 
-    @cmdutils.register(instance='browser', name='scroll_perc_x', hide=True)
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='scroll_perc_x',
+                       hide=True)
     def scroll_percent_x(self, perc=None, count=None):
         """Scroll the current tab to a specific percent of the page (horiz).
 
@@ -627,7 +627,8 @@ class CurCommandDispatcher(QObject):
         """
         self._scroll_percent(perc, count, Qt.Horizontal)
 
-    @cmdutils.register(instance='browser', name='scroll_perc_y', hide=True)
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='scroll_perc_y',
+                       hide=True)
     def scroll_percent_y(self, perc=None, count=None):
         """Scroll the current tab to a specific percent of the page (vert).
 
@@ -640,7 +641,7 @@ class CurCommandDispatcher(QObject):
         """
         self._scroll_percent(perc, count, Qt.Vertical)
 
-    @cmdutils.register(instance='browser', hide=True)
+    @cmdutils.register(instance='mainwindow.tabs.cur', hide=True)
     def scroll_page(self, mx, my, count=1):
         """Scroll the frame page-wise.
 
@@ -656,7 +657,7 @@ class CurCommandDispatcher(QObject):
         page.mainFrame().scroll(int(count) * float(mx) * size.width(),
                                 int(count) * float(my) * size.height())
 
-    @cmdutils.register(instance='browser')
+    @cmdutils.register(instance='mainwindow.tabs.cur')
     def yank(self, sel=False):
         """Yank the current url to the clipboard or primary selection.
 
@@ -676,7 +677,7 @@ class CurCommandDispatcher(QObject):
         self.temp_message.emit('URL yanked to {}'.format(
             'primary selection' if sel else 'clipboard'))
 
-    @cmdutils.register(instance='browser', name='yanktitle')
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='yanktitle')
     def yank_title(self, sel=False):
         """Yank the current title to the clipboard or primary selection.
 
@@ -696,7 +697,7 @@ class CurCommandDispatcher(QObject):
         self.temp_message.emit('Title yanked to {}'.format(
             'primary selection' if sel else 'clipboard'))
 
-    @cmdutils.register(instance='browser', name='zoomin')
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='zoomin')
     def zoom_in(self, count=1):
         """Zoom in in the current tab.
 
@@ -707,7 +708,7 @@ class CurCommandDispatcher(QObject):
         tab = self.tabs.currentWidget()
         tab.zoom(count)
 
-    @cmdutils.register(instance='browser', name='zoomout')
+    @cmdutils.register(instance='mainwindow.tabs.cur', name='zoomout')
     def zoom_out(self, count=1):
         """Zoom out in the current tab.