do not assume folders[0] is there

src/vs/workbench/parts/debug/browser/linkDetector.ts

@@ -37,6 +37,7 @@ export class LinkDetector {
 	 * If no links were detected, returns the original string.
 	 */
 	public handleLinks(text: string): HTMLElement | string {
+		const workspaceFolder = this.contextService.getWorkspace().folders[0];
 		let linkContainer: HTMLElement;
 
 		for (let pattern of LinkDetector.FILE_LOCATION_PATTERNS) {
@@ -46,7 +47,6 @@ export class LinkDetector {
 			let match = pattern.exec(text);
 			while (match !== null) {
 				let resource: uri = null;
-				const workspaceFolder = this.contextService.getWorkspace().folders[0];
 				if (workspaceFolder) {
 					try {
 						resource = (match && !strings.startsWith(match[0], 'http'))

src/vs/workbench/services/configuration/node/configuration.ts

@@ -555,7 +555,7 @@ export class WorkspaceService extends Disposable implements IWorkspaceConfigurat
 		if (this.getWorkbenchState() === WorkbenchState.EMPTY) {
 			this._onDidUpdateConfiguration.fire({ source: ConfigurationSource.User, sourceConfig: this._configuration.user.contents });
 		} else {
-			this._onDidUpdateConfiguration.fire({ source: ConfigurationSource.Workspace, sourceConfig: this._configuration.getFolderConfigurationModel(this.workspace.folders[0].uri).contents });
+			this._onDidUpdateConfiguration.fire({ source: ConfigurationSource.Workspace, sourceConfig: this.workspace.folders.length ? this._configuration.getFolderConfigurationModel(this.workspace.folders[0].uri).contents : void 0 }); // TODO@Sandeep debt?
 		}
 	}
 

src/vs/workbench/services/history/browser/history.ts

@@ -15,7 +15,7 @@ import { IWorkbenchEditorService } from 'vs/workbench/services/editor/common/edi
 import { IHistoryService } from 'vs/workbench/services/history/common/history';
 import { FileChangesEvent, IFileService, FileChangeType } from 'vs/platform/files/common/files';
 import { Selection } from 'vs/editor/common/core/selection';
-import { IWorkspaceContextService, WorkbenchState } from 'vs/platform/workspace/common/workspace';
+import { IWorkspaceContextService } from 'vs/platform/workspace/common/workspace';
 import { IDisposable, dispose } from 'vs/base/common/lifecycle';
 import { IStorageService, StorageScope } from 'vs/platform/storage/common/storage';
 import { ILifecycleService } from 'vs/platform/lifecycle/common/lifecycle';
@@ -766,7 +766,8 @@ export class HistoryService extends BaseHistoryService implements IHistoryServic
 	}
 
 	public getLastActiveWorkspaceRoot(): URI {
-		if (this.contextService.getWorkbenchState() === WorkbenchState.EMPTY) {
+		const folders = this.contextService.getWorkspace().folders;
+		if (folders.length === 0) {
 			return void 0;
 		}
 
@@ -785,6 +786,6 @@ export class HistoryService extends BaseHistoryService implements IHistoryServic
 		}
 
 		// fallback to first workspace
-		return this.contextService.getWorkspace().folders[0].uri;
+		return folders[0].uri;
 	}
 }