forceClearScrollbackBuffer conflicts with focusConsoleOnExecute #2313

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1. Sydney Smith (SydneyhSmith)

   added

   Issue-BugA bug to squash.A bug to squash.

   and removed

   Needs: TriageMaintainer attention needed!Maintainer attention needed!

   on Jul 28, 2020
2. SydneyhSmith commented on Jul 28, 2020

   

   Sydney Smith (SydneyhSmith)

   on Jul 28, 2020

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   I am thinking Rain Sallow (/u/ta11ow) (@vexx32) was having this issue, but I cant seem to find the bug
3. vexx32 commented on Jul 28, 2020

   

   Rain Sallow (/u/ta11ow) (vexx32)

   on Jul 28, 2020

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   I don't think this was the same thing I was seeing, though my issue did also concern how the console focusing logic worked (it was revealing + focusing the wrong console when I had it hiding the integrated console by default and also running debug sessions in new consoles every time, forget the exact setting names but yeah).

   👍React with 👍1Reacted by Sydney Smith
4. Sydney Smith (SydneyhSmith)

   removed

   Needs: Maintainer AttentionMaintainer attention needed!Maintainer attention needed!

   on Jul 30, 2020
6. Sydney Smith (SydneyhSmith)

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   Up for GrabsWill shepherd PRs.Will shepherd PRs.

   and removed

   Needs: Maintainer AttentionMaintainer attention needed!Maintainer attention needed!

   on Feb 9, 2021
7. andyleejordan commented on Jun 16, 2026

   

   Andy Jordan (andyleejordan)

   on Jun 16, 2026

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   Root cause and fix plan

   Picking this back up — the root cause is on the PowerShellEditorServices side, so I'm transferring this issue there to fix it. Summary of the investigation:

   Why it happens

   forceClearScrollbackBuffer exists because PSES's Clear-Host calls [Console]::Clear(), which clears the terminal viewport but not xterm.js's scrollback. To wipe scrollback, PSES round-trips an editor/clearTerminal notification to the extension, which runs workbench.action.terminal.clear. That workbench command always focuses the terminal — so every Clear-Host steals focus from the editor, even when focusConsoleOnExecute: false.

   Why we can't fix it cleanly in the extension

   The obvious client-side fix — "after clearing, restore focus to the editor only if an editor was focused" — isn't possible, because extension code can't read that condition:

   • window.activeTextEditor is "the one that currently has focus or, when none has focus, the one that changed input most recently" — so it stays defined when the terminal is focused; it can't distinguish editor-focused from terminal-focused.
   • TerminalState exposes only isInteractedWith + shell — no focus flag (and isInteractedWith is sticky).
   • window.activeTerminal is the active terminal, not the focused one.
   • terminalFocus / editorTextFocus are when-clause context keys only; there's no API to read a context key from code (CTRL+p stopped working microsoft/vscode#72647).
   • There's no Terminal.clear() and no focus-free clear command; only workbench.action.terminal.clear, which focuses.

   So the only client-side options are: restore focus unconditionally (regresses interactive Clear-Host/cls — typing it in the terminal now bounces focus to the editor) or do nothing (original bug). PR PowerShell/vscode-powershell#5519 took the unconditional route; that regression is why it's being closed.

   The fix (in PSES)

   Have PSES write the xterm "Erase Saved Lines" sequence (CSI 3 J = ESC[3J, i.e. \x1b[3J) directly to its own console output as part of Clear-Host, instead of round-tripping editor/clearTerminal. VS Code's integrated terminal is always xterm.js, which honors ESC[3J; the scrollback clears in-band with no focus change at all, in both the run-from-editor and the typed-in-terminal cases. No focus detection needed.

   This is safe because the extension↔PSES LSP runs over a named pipe/socket (not stdio), so PSES stdout is the terminal output and is separate from the LSP channel.

   Concrete plan:

   1. Map integratedConsole.forceClearScrollbackBuffer onto LanguageServerSettings (the extension already syncs the whole powershell config section via didChangeConfiguration).
   2. In Clear-Host / EditorOperationsService.ClearTerminal(), when that setting is true, write ESC[3J to the host output instead of sending editor/clearTerminal.
   3. In vscode-powershell (follow-up): remove the editor/clearTerminal handler once PSES lands; keep the forceClearScrollbackBuffer setting (now consumed server-side).

   Investigation drafted by Copilot for Andy Jordan (@andyleejordan).
8. Andy Jordan (andyleejordan)

   transferred this issue fromPowerShell/vscode-powershellon Jun 16, 2026