Thick white border around window when showTabsInTitlebar enabled

[dkter]

Environment

Windows build number: 10.0.18362.145
Windows Terminal version (if applicable):

Steps to reproduce

Set showTabsInTitlebar to true in the settings file, and then start up Windows Terminal.

Expected behavior

The window should be surrounded with a thin grey border:

Actual behavior

A thick, non-Windowsy white border is shown instead.

[DHowett-MSFT]

This will be addressed as part of #872.

Even though the issue was closed on Jun 18, I still have the same problem as described in the OP. My Windows build number is 18362.30 and my Windows Terminal version is 0.5.2681.0. Note that the border was still present when using the terminal on my Windows Insiders machine on the Fast update ring.

[zadjii-msft]

I'm gonna track this as part of #1625. I'm not sure that it's totally fixable in a good way, but I want to spend more time trying.