Being that this is a feature request by it’s very nature the function has not been implemented so I couldn’t say with certainty.
Though from what I can gather users are essentially asking for the same thing you are here, to “prompt to save” or otherwise give a pop-up warning if something isn’t saved. Or possibly have some type of “drafts” system where items that haven’t been completely saved will still be able to go back on to prevent data loss.
The request you link to asks for the UI to remember which entry you’re looking at when you switch to the app or webpage you’re using the information for (which would also prevent a great deal of frustration).
This request, I believe is to prevent you from exiting the entry by any means (whether clicking outside the pop-up in the web extension, or hitting the back button in the Android app, etc.) without being prompted to save changes when you’re editing an item.
I’ve lost count of the number of times I think I’ve updated important information and lost it because it’s way too easy to back out of the entry with the behaviour of “Cancel edits with no warning”.
This is data loss, which should be unforgiveable in an app designed to SAVE important data.