Can't change background color in Powershell after updating to 1809

[johanlindfors]

After the latest update to Windows 10 1809 I can't change the background color of the PowerShell console from within the actual console.

This used to work:

[console]::BackgroundColor = ”black”
Clear-Host
(the window was now black)

But it doesn't anymore.

[zadjii-msft]

I'll take a look at it. There's a good chance I regressed this. Internally filed as MSFT:19234722

[bitcrazed]

Thanks for filing @johanlindfors.

@zadjii-msft - I created bug 19221878 to track this.

[DHowett-MSFT]

[Linking] This was also reported at PowerShell/PSReadLine#774.

[lzybkr]

This happens because PSReadLine is writing CSI 0 m, you can reproduce w/o PSReadLine like this:

function prompt { "PS> " } # Ensure we aren't using posh-git
[Console]::BackgroundColor = 'Yellow'
cls
"$([char]0x1b)[34mHello$([char]0x1b)[0m"
"$([char]0x1b)[34mHello$([char]0x1b)[0m"

After the cls, I have the follow

So it looks like writing CSI 0 m reverts the background color to the initial background color, not the current background color (which may have been set via an escape sequence or via a Win32 Console api).

It also looks like this behavior is not specific to conhost, I see the same thing in the CentOS Terminal.

So is it safe to say that any tool that writes CSI 0 m should save the current foreground/background colors before writing anything and restore them afterwards? Assuming this is correct, Posh-Git and maybe Powerline also need to be fixed.

[mjoyce6500]

Experiencing same issue after OS update. Custom $PROFILE which was working now reverts back to system default background color at the prompt as you type ….