Running Far Manager under winpty sometimes shows a blank turquoise screen

[rprichard]

I'm running WINPTY_SHOW_CONSOLE=1 WINPTY_DEBUG=trace build/winpty /c/bin64/Far30b4545/Far.exe

Far Manager, version 3.0 (build 4545) x64
Copyright © 1996-2000 Eugene Roshal, Copyright © 2000-2016 Far Group

$ WINPTY_SHOW_CONSOLE=1 WINPTY_DEBUG=trace build/winpty --version
winpty version 0.4.3-dev
commit bae43674b1944b66eb06481424fa73d9333c44cd

It looks like Far Manager doesn't change the console window or buffer sizes (anymore?). It does, however, place the Far Manager GUI at the bottom of the 3000-line console buffer, which seems unusual to me, but I don't know why that wouldn't work.

I resized the underlying console's font by hand to make it more readable.

[rprichard]

During startup, Far Manager moves the window to the bottom of the buffer, but it takes a while longer to move the cursor to the bottom of the buffer. Here's what happens:

1. Scraper sends virtual lines 0-2999 (inclusive) to Terminal, which contains the correctly drawn Far Manager GUI at the end.
2. Scraper shows the cursor at virtual line 0. Terminal sends 2999 CUrsor Up (CUU) VT/100 commands.
3. Scraper eventually moves the cursor to line 2998. Terminal sends 2998 CRLN commands.
4. Everything on the terminal scrolls up and away.

winpty can already hide the cursor. It should probably hide the cursor if it isn't inside the console window.