Detaching a discarded tab and attaching to a new window causes a duplicate navigation entry to be added

[petemill]

...and scroll position / input entry state to be lost.
Discovered whilst testing #504

STR

Make sure you have #504 and brave/browser-laptop#13120
Login to github.com
Visit http://github.com/brave/browser-laptop/issues/new
Enter "TEST" at the top of the issue description
Switch to another tab
Right-click the github issue tab and select 'Discard'
Right-click the github issue tab (be careful not to trigger a preview) and choose 'Detach'

Actual

The detached, and now reloaded tab, does not contain the word "TEST" at the top of the issue description.
The tab now has a additional 'back' navigation entry to the same Url.

Expected

The draft description is preserved.
This works when discarding a tab and then making it active, causing a reload. The draft content is preserved. Adding the action of a detach and then attach to a new window is causing some data to be lost.

Tested that session storage, local storage and session cookies are preserved ✅