fix #107239, set terminal dimensions

src/vs/vscode.d.ts

@@ -9273,7 +9273,7 @@ declare module 'vscode' {
 		 * Implement to handle when the number of rows and columns that fit into the terminal panel
 		 * changes, for example when font size changes or when the panel is resized. The initial
 		 * state of a terminal's dimensions should be treated as `undefined` until this is triggered
-		 * as the size of a terminal isn't know until it shows up in the user interface.
+		 * as the size of a terminal isn't known until it shows up in the user interface.
 		 *
 		 * When dimensions are overridden by
 		 * [onDidOverrideDimensions](#Pseudoterminal.onDidOverrideDimensions), `setDimensions` will

src/vs/workbench/api/common/extHostTerminalService.ts

@@ -250,6 +250,11 @@ export class ExtHostPseudoterminal implements ITerminalChildProcess {
 		}
 
 		this._pty.open(initialDimensions ? initialDimensions : undefined);
+
+		if (this._pty.setDimensions && initialDimensions) {
+			this._pty.setDimensions(initialDimensions);
+		}
+
 		this._onProcessReady.fire({ pid: -1, cwd: '' });
 	}
 }