Revert "old qt: Remove networkmanager init workaround"

See #6010
This reverts commit 0810b3e7b99316861bf9e34c694136c30e1a2266.

2 files changed, 16 insertions, 1 deletions

diff --git a/qutebrowser/browser/webkit/network/networkmanager.py b/qutebrowser/browser/webkit/network/networkmanager.py
index 3e393680c..a1ef0463d 100644
--- a/qutebrowser/browser/webkit/network/networkmanager.py
+++ b/qutebrowser/browser/webkit/network/networkmanager.py
@@ -155,7 +155,12 @@ class NetworkManager(QNetworkAccessManager):
 
     def __init__(self, *, win_id, tab_id, private, parent=None):
         log.init.debug("Initializing NetworkManager")
-        super().__init__(parent)
+        with log.disable_qt_msghandler():
+            # WORKAROUND for a hang when a message is printed - See:
+            # http://www.riverbankcomputing.com/pipermail/pyqt/2014-November/035045.html
+            #
+            # Still needed on Qt/PyQt 5.15.2 according to #6010.
+            super().__init__(parent)
         log.init.debug("NetworkManager init done")
         self.adopted_downloads = 0
         self._win_id = win_id
diff --git a/qutebrowser/utils/log.py b/qutebrowser/utils/log.py
index 9aedb419f..fa6d9beaf 100644
--- a/qutebrowser/utils/log.py
+++ b/qutebrowser/utils/log.py
@@ -234,6 +234,16 @@ def _init_py_warnings() -> None:
 
 
 @contextlib.contextmanager
+def disable_qt_msghandler() -> Iterator[None]:
+    """Contextmanager which temporarily disables the Qt message handler."""
+    old_handler = QtCore.qInstallMessageHandler(None)
+    try:
+        yield
+    finally:
+        QtCore.qInstallMessageHandler(old_handler)
+
+
+@contextlib.contextmanager
 def py_warning_filter(action: str = 'ignore', **kwargs: Any) -> Iterator[None]:
     """Contextmanager to temporarily disable certain Python warnings."""
     warnings.filterwarnings(action, **kwargs)