Crash or rendering broken when changing tab while a download starts

I have an app with a QWebEngineView and multiple pages.

Step to reproduce:

1. User has 2 pages and the 2nd page is displayed in the view
2. From the 2nd page, the user triggers a download that takes a couple of second to actually start
3. User switch to page 1
4. Page 2 opens the download link in a 3rd page
5. The download starts from the 3rd page
6. User switch back to the 2nd page
7. The 2nd page is gone, only whit is displayed

Alternatively

1. User has 2 pages and the 2nd page is displayed in the view
2. From the 2nd page, the user triggers a download that takes a couple of second to actually start
3. User switch to page 1
4. Page 2 opens the download link in a 3rd page
5. The download starts from the 3rd page
6. The app detects that the 3rd page was created just to trigger a download and deletes the 3rd page
7. User switch back to the 2nd page
8. Crash

The crash happens systematically in QWebEngineViewPrivate::bindPageAndView()
From what I could collect it is because a pointer to a deleted RenderWidgetHostViewQtDelegateItem is being used.