src/vs/workbench/contrib/search/browser/searchWidget.ts/SearchWidget/updateReplaceActiveState
class SearchWidget:	private updateReplaceActiveState(): void {
		const currentState = this.isReplaceActive();
		const newState = this.isReplaceShown() && this.replaceAllAction.enabled;
		if (currentState !== newState) {
			this.replaceActive.set(newState);
			this._onReplaceStateChange.fire(newState);
			this.replaceInput.inputBox.layout();
		}
	}