Rework of selectionBackground & addition of selectionForeground

[linuxluzer]

While making the new WT look and feel like Powershell, the selectionBackground property seems affected by an acrylic effect that reduces contrast for accessibility and causes an ugly sensation whit some color schemes. It should be a true/false option that triggers the cmd/powershell mode (full opacity). In that case, a selectionForeground could be added too, in order to address the parity features with conhost.exe.

A technical implementation in profiles.json could be something like this (don´t have enough C++ knowledge for real code):

"profiles":
    {
        "list":
        [
            {
                "name": "Windows PowerShell",
                "commandline": "powershell.exe",
                "selectionOpacity": true,
                "selectionBackground": "#fedba9",
                "selectionForeground": "#ffffff",
                "hidden": false
             }
        ]
    }

[DHowett-MSFT]

Thanks for the request! This is, at its heart, a /dupe of #3580 and #3561. 😄

[ghost]

Hi! We've identified this issue as a duplicate of another one that already exists on this Issue Tracker. This specific instance is being closed in favor of tracking the concern over on the referenced thread. Thanks for your report!