Yes, I know exactly the issue you are referring to, but sadly not the solution.
I have seen it occasionally, but never consistently enough to trace. I “think” therefore it’s somehow related to the browser, rather than kiwitrees – or perhaps that’s just wishful thinking.
Browsers can have different behaviors on open and close. I’ve also wondered if it’s related to the number in use, where each originated (the tab used to open each new one, or perhaps something with the browser cache.
So if you can help narrow it down in any way that would be very useful.
Does it an in different browsers, or different versions of a single browser? Does the number of tabs in use make a difference? Does clearing the browser cache help?
I do know it’s not a new issue. I’ve seen it occasionally ever since the new edit tabs were introduced.