[Python] Repeatedly open/interact with/close PyQt6.QtWebEngineWidgets.QWebEngineView widgets

EDIT: I reformulated my question in a hopefully clearer way. Please see: Repeatedly create/delete a PyQt6.QtWebEngineWidgets.QWebEngineView widget


I would like to open/interact_with a PyQt6.QtWebEngineWidgets.QWebEngineView widget, then close it, then open/interact_with a new one... each time using a new QApplication (it is important that, once done using a given QWebEngineView instance, there should be no QApplication instance to avoid interference with other GUI toolkits). Here is a toy example to illustrate my goal:

# New app in each loop / QWebEngineView => crashes
import sys
from PyQt6.QtWebEngineWidgets import QWebEngineView as widget_t
from PyQt6.QtWidgets import QApplication as application_t

html = """
<!DOCTYPE html>
<html>
<body>
<h1>Content Title</h1>
<p>Content.</p>
</body>
</html>
"""

for _ in range(2):
application = application_t(sys.argv)

widget = widget_t()
widget.setHtml(html)
widget.show()

application.exec()
del application # Found in a discussion that this was necessary.


This sample code crashes (in Qt) during the second iteration. (I read many discussions about properly closing a QWebEngineView, and did some attempts to follow the recommendations.) What seems to be the problem is the combination QWebEngineView+"new QApplication". If I use a QLabel, it works:

# New app in each loop / QLabel => works
import sys
from PyQt6.QtWidgets import QLabel as widget_t
from PyQt6.QtWidgets import QApplication as application_t

for _ in range(2):
application = application_t(sys.argv)

widget = widget_t("Content")
widget.show()

application.exec()
del application # Found in a discussion that this was necessary.


If I use the same QApplication in each loops, it also works:

# Same app in each loop / QWebEngineView => works
import sys
from PyQt6.QtWebEngineWidgets import QWebEngineView as widget_t
from PyQt6.QtWidgets import QApplication as application_t

html = """
<!DOCTYPE html>
<html>
<body>
<h1>Content Title</h1>
<p>Content.</p>
</body>
</html>
"""

application = application_t(sys.argv)
for _ in range(2):
widget = widget_t()
widget.setHtml(html)
widget.show()

application.exec()


How can I transform the "New app in each loop / QWebEngineView => crashes" code above into a "New app in each loop / QWebEngineView => works" version?

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