Using Chrome Flags With Qtwebengine (pyqt5)

For the development of my PyQt5 browser project, I read here that by passing Chrome flags as application arguments, they will automatically be passed onto the QtWebEngineProcess.ex

Solution 1:

To set the chromium flags can be done using the following methods(See the docs):

• Pass as arguments to QApplication:

  args = ["--foo-arg=foo-value", "--bar-arg=bar-value"]
  app = QtWidgets.QApplication(args)
  # or # app = QtWidgets.QApplication(sys.argv + args)

• Set it through the environment variable QTWEBENGINE_CHROMIUM_FLAGS:

  import os
  
  os.environ["QTWEBENGINE_CHROMIUM_FLAGS"] = "--foo-arg=foo-value --bar-arg=bar-value"
  app = QtWidgets.QApplication(sys.argv)
  

And therefore your attempt is correct but the problem seems to be that not all chromium flags are supported by Qt WebEngine and that seems to be the case for --enable-force-dark. Searching the net I found this post that provides an alternative: --blink-settings=darkMode=4,darkModeImagePolicy=2

from PyQt5 import QtCore, QtWidgets, QtWebEngineWidgets

if __name__ == "__main__":
    import os
    import sys

    os.environ[
        "QTWEBENGINE_CHROMIUM_FLAGS"
    ] = "--blink-settings=darkMode=4,darkModeImagePolicy=2"
    app = QtWidgets.QApplication(sys.argv)

    # or# args = sys.argv + ["--blink-settings=darkMode=4,darkModeImagePolicy=2"]# app = QtWidgets.QApplication(sys.argv + args)

    view = QtWebEngineWidgets.QWebEngineView()
    view.load(QtCore.QUrl("https://www.google.com"))
    view.show()
    sys.exit(app.exec_())