Scroll up/down (SU/SD) don't copy wide glyph padding spaces

[lhecker]

Windows Terminal version

No response

Windows build number

No response

Other Software

No response

Steps to reproduce

• pwsh

  "`e[?1049h`e[Hbefore scroll`e[999C`e[2Dfoo`r`n`e[999C`e[2D✨✨"; sleep 1; "`e[S`e[Hafter scroll "; sleep 3; "`e[?1049l"
  

• bash

  printf "\e[?1049h\e[Hbefore scroll\e[999C\e[2Dfoo\r\n\e[999C\e[2D✨✨"; sleep 1; printf "\e[S\e[Hafter scroll "; sleep 3; printf "\e[?1049l"
  

Expected Behavior

Actual Behavior

The fundamental problem is that ROW::CopyFrom doesn't clear to the end of the line (like CSI K).