I’m able to reproduce this with the ADW Launcher 2. Whenever I use Add to Homescreen, it adds the shortcut to my Pixel 2 XL native homescreen.
From what I’m reading, it looks like several ‘third-party’ launchers have the issue in newer Android versions. It’s odd that the issue exists on the built-in OnePlus launcher.
Depending on what you are trying to accomplish, there may be some workaround with either Fully Kiosk Browser, WallPanel, or Anker (the latter generating a simple wrapper for a site whereas the first two are more frequently used as dedicated dashboard displays)