Who should use Stack Peak?

Stack Peak is a consumer product built for web developers and CSS authors.

Yes — Stack Peak is free to use.

What platforms does Stack Peak run on?

Stack Peak runs on the web, embeddable surfaces, macOS, Windows, and Linux.

Is Stack Peak still active?

Unverified. Stack Peak has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

Who makes Stack Peak?

Stack Peak is developed by Jack J. Watson.

When did Stack Peak launch?

Stack Peak first shipped in 2026.

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Stack Peak

Name: Stack Peak
Author: Jack J. Watson

mozilla.orgBrowser DevTools & extensions

Stack Peak is a Firefox browser extension for selecting the next CSS z-index value. Users paste a stack of integer layers, and the extension suggests the next value without collecting data.

FreeWebEmbeddablemacOSWindowsLinux

Visit mozilla.org

Overview

4 features

Stack Peak is a Browser DevTools & extensions project. It focuses on choosing the next available CSS z-index without manually inspecting existing integer layers. It is built as a consumer product for web developers and CSS authors. Stack Peak is free to use. It ships for the web, embeddable surfaces, macOS, Windows, and Linux.

It is developed by Jack J. Watson, and it first shipped in 2026. Among its 4 catalogued features are Z-index suggestions, integer stack input, and firefox integration. The interface is available in 32 languages, including Czech, German, and Greek.

Summary written by a language model from the project’s public pages.

Z-index suggestions
Integer stack input
Firefox integration
No data collection

Built with & integrations

Runs on

BrowserEmbeddablemacOSWindowsLinux

Trust & compliance

Verified signals

HTTPSPrivacy Policy Terms of ServiceFree tierMulti-languageStore-verified publisher

Legal

Indexing history

What PulseGate has recorded for this listing

Indexed4 Sept · 22:00 UTC
Stack Peak verified via Firefox Add-ons
Source: Firefox Add-ons · Open

Frequently asked questions about Stack Peak

What is Stack Peak?: Stack Peak focuses on choosing the next available CSS z-index without manually inspecting existing integer layers. It is catalogued under Browser DevTools & extensions on PulseGate.
Who should use Stack Peak?: Stack Peak is a consumer product built for web developers and CSS authors.
Is Stack Peak free?: Yes — Stack Peak is free to use.
What platforms does Stack Peak run on?: Stack Peak runs on the web, embeddable surfaces, macOS, Windows, and Linux.
Is Stack Peak still active?: Unverified. Stack Peak has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
Who makes Stack Peak?: Stack Peak is developed by Jack J. Watson.
When did Stack Peak launch?: Stack Peak first shipped in 2026.
What languages does Stack Peak support?: The interface is available in 32 languages, including Czech, German, and Greek.

At a glance

Pricing: Free
Platforms: Web
First seen: 4 Sept 2026
Built for: web developers and CSS authors
Model: B2C
Solves: Choosing the next available CSS z-index without manually inspecting existing integer layers.

Registered as

Firefox Add-ons: stack-peak

Developer

Jack J. Watson

Index record

Indexed: 4 Sept 2026
Lifecycle: Alive
First seen: Sept 2026
Last seen: 4 Sept 2026

Identity audit (13)

Slug: stack-peak-mozilla-org
Lifecycle last checked: 8 Sept 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 4 Sept 2026
Timeline basis: Indexed-at chronology (no inferred launch/funding milestones).
Name from: Derived from the project's own page and URL.
Category from: Assigned by a language model.
Summary from: Written by a language model from public pages.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 4 Sept 2026
Canonical URL: https://addons.mozilla.org/en-US/firefox/addon/stack-peak

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