Search is often broken while console process is running

[asklar]

Environment

Windows build number: 10.0.18362.113
Windows Terminal version (if applicable):

Any other software?

Steps to reproduce

have a long running process (e.g. msbuild), and ctrl+F to find something. Often the match will be off by one line
10.0.18362.113

Expected behavior

I can find the text properly

Actual behavior

The text that gets selected when searching is not the right text

[asklar]

note that the line that conhost selects is not the one with the text "file not found" (not shown since the buffer scrolled) but the next one.

[DHowett-MSFT]

This is probably not a new regression; I think we probably broke this in RS5.

[zadjii-msft]

Pretty sure this is fixed by #15858

[zadjii-msft]

This didn't look fixed in the conhost in 26051.1000.amd64fre.ge_release_we_adept.240201-1823. I don't know if that has the FI including the updated console code from main though.

But also: that doesn't seem to matter. Still broken in openconsole as of ef96e22.