Poor user experience with git subrepos.

When navigating the repo history with a git subrepos there are multiple popups of a command prompt window. They go away as soon as they appear, but they're quite obnoxious and distracting. I'm sure that they're doing important work in the background, but there should be a way to do this without opening new command prompt windows. When I run hg status or hg diff myself I don't get these, so I assume they are not coming from Mercurial itself.

I'd be willing to take a look at fixing this myself if someone could point me in the right direction (what code is causing this).

I'm using TortoiseHG v5.9.2.