diff --git a/extensions/git/package.json b/extensions/git/package.json
index 17e8de43d3841..e9e667dcc337b 100644
--- a/extensions/git/package.json
+++ b/extensions/git/package.json
@@ -88,7 +88,7 @@
         "command": "git.reopenClosedRepositories",
         "title": "%command.reopenClosedRepositories%",
         "category": "Git",
-        "enablement": "!operationInProgress && git.ClosedRepositoryCount != 0"
+        "enablement": "!operationInProgress && git.closedRepositoryCount != 0"
       },
       {
         "command": "git.close",
diff --git a/extensions/git/src/model.ts b/extensions/git/src/model.ts
index 48f3a5c43e60b..3315b3eee5881 100644
--- a/extensions/git/src/model.ts
+++ b/extensions/git/src/model.ts
@@ -19,7 +19,6 @@ import { ApiRepository } from './api/api1';
 import { IRemoteSourcePublisherRegistry } from './remotePublisher';
 import { IPostCommitCommandsProviderRegistry } from './postCommitCommands';
 import { IBranchProtectionProviderRegistry } from './branchProtection';
-import { ObservableSet } from './observable';
 
 class RepositoryPick implements QuickPickItem {
 	@memoize get label(): string {
@@ -93,6 +92,42 @@ interface OpenRepository extends Disposable {
 	repository: Repository;
 }
 
+class ClosedRepositoriesManager {
+
+	private _repositories: Set<string>;
+	get repositories(): string[] {
+		return [...this._repositories.values()];
+	}
+
+	constructor(private readonly workspaceState: Memento) {
+		this._repositories = new Set<string>(workspaceState.get<string[]>('closedRepositories', []));
+		this.onDidChangeRepositories();
+	}
+
+	addRepository(repository: string): void {
+		this._repositories.add(repository);
+		this.onDidChangeRepositories();
+	}
+
+	deleteRepository(repository: string): boolean {
+		const result = this._repositories.delete(repository);
+		if (result) {
+			this.onDidChangeRepositories();
+		}
+
+		return result;
+	}
+
+	isRepositoryClosed(repository: string): boolean {
+		return this._repositories.has(repository);
+	}
+
+	private onDidChangeRepositories(): void {
+		this.workspaceState.update('closedRepositories', [...this._repositories.values()]);
+		commands.executeCommand('setContext', 'git.closedRepositoryCount', this._repositories.size);
+	}
+}
+
 export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePublisherRegistry, IPostCommitCommandsProviderRegistry, IPushErrorHandlerRegistry {
 
 	private _onDidOpenRepository = new EventEmitter<Repository>();
@@ -170,9 +205,9 @@ export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePu
 		return this._parentRepositories;
 	}
 
-	private _closedRepositories: ObservableSet<string>;
+	private _closedRepositoriesManager: ClosedRepositoriesManager;
 	get closedRepositories(): string[] {
-		return [...this._closedRepositories.values()];
+		return [...this._closedRepositoriesManager.repositories];
 	}
 
 	/**
@@ -187,10 +222,9 @@ export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePu
 
 	private disposables: Disposable[] = [];
 
-	constructor(readonly git: Git, private readonly askpass: Askpass, private globalState: Memento, private workspaceState: Memento, private logger: LogOutputChannel, private telemetryReporter: TelemetryReporter) {
-		this._closedRepositories = new ObservableSet<string>(workspaceState.get<string[]>('closedRepositories', []));
-		this._closedRepositories.onDidChange(this.onDidChangeClosedRepositories, this, this.disposables);
-		this.onDidChangeClosedRepositories();
+	constructor(readonly git: Git, private readonly askpass: Askpass, private globalState: Memento, readonly workspaceState: Memento, private logger: LogOutputChannel, private telemetryReporter: TelemetryReporter) {
+		// Repositories managers
+		this._closedRepositoriesManager = new ClosedRepositoriesManager(workspaceState);
 
 		workspace.onDidChangeWorkspaceFolders(this.onDidChangeWorkspaceFolders, this, this.disposables);
 		window.onDidChangeVisibleTextEditors(this.onDidChangeVisibleTextEditors, this, this.disposables);
@@ -379,11 +413,6 @@ export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePu
 		openRepositoriesToDispose.forEach(r => r.dispose());
 	}
 
-	private onDidChangeClosedRepositories(): void {
-		this.workspaceState.update('closedRepositories', [...this._closedRepositories.values()]);
-		commands.executeCommand('setContext', 'git.closedRepositoryCount', this._closedRepositories.size);
-	}
-
 	private async onDidChangeVisibleTextEditors(editors: readonly TextEditor[]): Promise<void> {
 		if (!workspace.isTrusted) {
 			this.logger.trace('[svte] Workspace is not trusted.');
@@ -496,7 +525,7 @@ export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePu
 			}
 
 			// Handle repositories that were closed by the user
-			if (!openIfClosed && this._closedRepositories.has(repositoryRoot)) {
+			if (!openIfClosed && this._closedRepositoriesManager.isRepositoryClosed(repositoryRoot)) {
 				this.logger.trace(`Repository for path ${repositoryRoot} is closed`);
 				return;
 			}
@@ -506,7 +535,7 @@ export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePu
 			const repository = new Repository(this.git.open(repositoryRoot, dotGit, this.logger), this, this, this, this, this.globalState, this.logger, this.telemetryReporter);
 
 			this.open(repository);
-			this._closedRepositories.delete(repository.root);
+			this._closedRepositoriesManager.deleteRepository(repository.root);
 
 			// Do not await this, we want SCM
 			// to know about the repo asap
@@ -658,7 +687,7 @@ export class Model implements IBranchProtectionProviderRegistry, IRemoteSourcePu
 		}
 
 		this.logger.info(`Close repository: ${repository.root}`);
-		this._closedRepositories.add(openRepository.repository.root.toString());
+		this._closedRepositoriesManager.addRepository(openRepository.repository.root);
 
 		openRepository.dispose();
 	}
diff --git a/extensions/git/src/observable.ts b/extensions/git/src/observable.ts
deleted file mode 100644
index b32fbf156dd3f..0000000000000
--- a/extensions/git/src/observable.ts
+++ /dev/null
@@ -1,70 +0,0 @@
-/*---------------------------------------------------------------------------------------------
- *  Copyright (c) Microsoft Corporation. All rights reserved.
- *  Licensed under the MIT License. See License.txt in the project root for license information.
- *--------------------------------------------------------------------------------------------*/
-
-import { EventEmitter } from 'vscode';
-
-export class ObservableSet<T> implements Set<T> {
-
-	readonly [Symbol.toStringTag]: string = 'ObservableSet';
-
-	private _set: Set<T>;
-	private _onDidChange = new EventEmitter<void>();
-	readonly onDidChange = this._onDidChange.event;
-
-	constructor(values?: readonly T[] | null) {
-		this._set = new Set(values);
-	}
-
-	get size(): number {
-		return this._set.size;
-	}
-
-	add(value: T): this {
-		this._set.add(value);
-		this._onDidChange.fire();
-
-		return this;
-	}
-
-	clear(): void {
-		if (this._set.size > 0) {
-			this._set.clear();
-			this._onDidChange.fire();
-		}
-	}
-
-	delete(value: T): boolean {
-		const result = this._set.delete(value);
-		if (result) {
-			this._onDidChange.fire();
-		}
-
-		return result;
-	}
-
-	forEach(callbackfn: (value: T, value2: T, set: Set<T>) => void, thisArg?: any): void {
-		this._set.forEach((_value, key) => callbackfn.call(thisArg, key, key, this));
-	}
-
-	has(value: T): boolean {
-		return this._set.has(value);
-	}
-
-	entries(): IterableIterator<[T, T]> {
-		return this._set.entries();
-	}
-
-	keys(): IterableIterator<T> {
-		return this._set.keys();
-	}
-
-	values(): IterableIterator<T> {
-		return this._set.keys();
-	}
-
-	[Symbol.iterator](): IterableIterator<T> {
-		return this.keys();
-	}
-}