Prevent :home from bypassing pinned tab warnings

Closes #3138

qutebrowser/browser/commands.py

@@ -353,6 +353,10 @@ class CommandDispatcher:
         Return:
             A list of URLs that can be opened.
         """
+        if isinstance(url, QUrl):
+            yield url
+            return
+
         force_search = False
         urllist = [u for u in url.split('\n') if u.strip()]
         if (len(urllist) > 1 and not urlutils.is_url(urllist[0]) and
@@ -1210,7 +1214,7 @@ class CommandDispatcher:
     @cmdutils.register(instance='command-dispatcher', scope='window')
     def home(self):
         """Open main startpage in current tab."""
-        self._current_widget().openurl(config.val.url.start_pages[0])
+        self.openurl(config.val.url.start_pages[0])
 
     def _run_userscript(self, cmd, *args, verbose=False):
         """Run a userscript given as argument.

tests/end2end/features/tabs.feature

@@ -1197,6 +1197,14 @@ Feature: Tab management
         And the following tabs should be open:
             - data/numbers/1.txt (active) (pinned)
 
+    Scenario: :tab-pin open url
+        When I open data/numbers/1.txt
+        And I run :tab-pin
+        And I run :home
+        Then the message "Tab is pinned!" should be shown
+        And the following tabs should be open:
+            - data/numbers/1.txt (active) (pinned)
+
     Scenario: Cloning a pinned tab
         When I open data/numbers/1.txt
         And I run :tab-pin