diff --git a/src/commands/closeUnchangedFiles.ts b/src/commands/closeUnchangedFiles.ts
index e984ad1..499bb51 100644
--- a/src/commands/closeUnchangedFiles.ts
+++ b/src/commands/closeUnchangedFiles.ts
@@ -130,7 +130,7 @@ export class CloseUnchangedFilesCommand extends Command {
 
 	private waitForEditorChange(timeout: number = 500): Promise<TextEditor | undefined> {
 		return new Promise<TextEditor | undefined>(resolve => {
-			let timer: any | undefined;
+			let timer: ReturnType<typeof setTimeout> | undefined;
 
 			this._onEditorChangedFn = (editor: TextEditor | undefined) => {
 				if (timer != null) {
diff --git a/src/partners.ts b/src/partners.ts
index 4fc58ce..01cf40b 100644
--- a/src/partners.ts
+++ b/src/partners.ts
@@ -12,12 +12,15 @@ export async function installExtension<T>(
 	vsix?: Uri,
 ): Promise<Extension<T> | undefined> {
 	try {
-		let timer: any = 0;
+		let timer: ReturnType<typeof setTimeout> | undefined = undefined;
 		const extension = new Promise<Extension<any> | undefined>(resolve => {
 			const disposable = extensions.onDidChange(() => {
 				const extension = extensions.getExtension(extensionId);
 				if (extension != null) {
-					clearTimeout(timer);
+					if (timer != null) {
+						clearTimeout(timer);
+						timer = undefined;
+					}
 					disposable.dispose();
 
 					resolve(extension);
@@ -33,7 +36,10 @@ export async function installExtension<T>(
 
 		await commands.executeCommand(BuiltInCommands.InstallExtension, vsix ?? extensionId);
 		// Wait for extension activation until timeout expires
-		timer = setTimeout(() => tokenSource.cancel(), timeout);
+		timer = setTimeout(() => {
+			timer = undefined;
+			tokenSource.cancel();
+		}, timeout);
 
 		return extension;
 	} catch {
diff --git a/src/statusbar/statusBarController.ts b/src/statusbar/statusBarController.ts
index 9cd202a..cee920c 100644
--- a/src/statusbar/statusBarController.ts
+++ b/src/statusbar/statusBarController.ts
@@ -25,7 +25,7 @@ import { LinesChangeEvent } from '../trackers/gitLineTracker';
 export class StatusBarController implements Disposable {
 	private _pullRequestCancellation: CancellationTokenSource | undefined;
 	private _tooltipCancellation: CancellationTokenSource | undefined;
-	private _tooltipDelayTimer: any | undefined;
+	private _tooltipDelayTimer: ReturnType<typeof setTimeout> | undefined;
 
 	private readonly _disposable: Disposable;
 	private _statusBarBlame: StatusBarItem | undefined;
@@ -305,10 +305,13 @@ export class StatusBarController implements Disposable {
 
 		this._statusBarBlame.tooltip = tooltip;
 
-		clearTimeout(this._tooltipDelayTimer);
+		if (this._tooltipDelayTimer != null) {
+			clearTimeout(this._tooltipDelayTimer);
+		}
 		this._tooltipCancellation?.cancel();
 
 		this._tooltipDelayTimer = setTimeout(() => {
+			this._tooltipDelayTimer = undefined;
 			this._tooltipCancellation = new CancellationTokenSource();
 
 			void this.updateCommitTooltip(
diff --git a/src/system/function.ts b/src/system/function.ts
index 61d74da..f846157 100644
--- a/src/system/function.ts
+++ b/src/system/function.ts
@@ -152,26 +152,26 @@ export function propOf<T, K extends Extract<keyof T, string>>(o: T, key: K) {
 }
 
 export function interval(fn: (...args: any[]) => void, ms: number): Disposable {
-	let timer: any | undefined;
+	let timer: ReturnType<typeof setInterval> | undefined;
 	const disposable = {
 		dispose: () => {
-			if (timer !== undefined) {
+			if (timer != null) {
 				clearInterval(timer);
 				timer = undefined;
 			}
 		},
 	};
-	timer = globalThis.setInterval(fn, ms);
+	timer = setInterval(fn, ms);
 
 	return disposable;
 }
 
 export function progress<T>(promise: Promise<T>, intervalMs: number, onProgress: () => boolean): Promise<T> {
 	return new Promise((resolve, reject) => {
-		let timer: any | undefined;
-		timer = globalThis.setInterval(() => {
+		let timer: ReturnType<typeof setInterval> | undefined;
+		timer = setInterval(() => {
 			if (onProgress()) {
-				if (timer !== undefined) {
+				if (timer != null) {
 					clearInterval(timer);
 					timer = undefined;
 				}
@@ -180,7 +180,7 @@ export function progress<T>(promise: Promise<T>, intervalMs: number, onProgress:
 
 		promise.then(
 			() => {
-				if (timer !== undefined) {
+				if (timer != null) {
 					clearInterval(timer);
 					timer = undefined;
 				}
@@ -188,7 +188,7 @@ export function progress<T>(promise: Promise<T>, intervalMs: number, onProgress:
 				resolve(promise);
 			},
 			ex => {
-				if (timer !== undefined) {
+				if (timer != null) {
 					clearInterval(timer);
 					timer = undefined;
 				}
diff --git a/src/system/promise.ts b/src/system/promise.ts
index 62a113f..9972e65 100644
--- a/src/system/promise.ts
+++ b/src/system/promise.ts
@@ -28,9 +28,9 @@ export function cancellable<T>(
 
 	return new Promise((resolve, reject) => {
 		let fulfilled = false;
-		let timer: any | undefined;
+		let timer: ReturnType<typeof setTimeout> | undefined;
 		if (typeof timeoutOrToken === 'number') {
-			timer = globalThis.setTimeout(() => {
+			timer = setTimeout(() => {
 				if (typeof options.onDidCancel === 'function') {
 					options.onDidCancel(resolve, reject);
 				} else {
@@ -52,14 +52,14 @@ export function cancellable<T>(
 		promise.then(
 			() => {
 				fulfilled = true;
-				if (timer !== undefined) {
+				if (timer != null) {
 					clearTimeout(timer);
 				}
 				resolve(promise);
 			},
 			ex => {
 				fulfilled = true;
-				if (timer !== undefined) {
+				if (timer != null) {
 					clearTimeout(timer);
 				}
 				reject(ex);
diff --git a/src/trackers/documentTracker.ts b/src/trackers/documentTracker.ts
index f3992f3..aad0ca6 100644
--- a/src/trackers/documentTracker.ts
+++ b/src/trackers/documentTracker.ts
@@ -96,7 +96,7 @@ export class DocumentTracker<T> implements Disposable {
 		this.onActiveTextEditorChanged(window.activeTextEditor);
 	}
 
-	private _timer: any | undefined;
+	private _timer: ReturnType<typeof setTimeout> | undefined;
 	private onActiveTextEditorChanged(editor: TextEditor | undefined) {
 		if (editor != null && !isTextEditor(editor)) return;