Cookie Policy
What cookies and browser storage DM Companion uses and why.
Last Updated
March 22, 2026
Overview
DM Companion is committed to transparency about data stored in your browser. This policy explains what cookies, localStorage, and sessionStorage we use, their purpose, and how to manage them.
We do not use any cookies for tracking, advertising, or analytics.
Authentication Cookies
These cookies are set by our authentication provider, Supabase, and are essential for the app to function.
| Cookie | Purpose | Duration | Type |
|---|---|---|---|
sb-access-token |
Keeps you signed in (JWT access token) | 1 hour | Essential |
sb-refresh-token |
Refreshes your session without re-login | 7 days | Essential |
These cookies are strictly necessary for the app to work. Without them, you cannot stay signed in.
Local Storage
DM Companion uses your browser's localStorage to save your data and preferences locally. This data never leaves your device.
| Key Pattern | Purpose | Duration |
|---|---|---|
dm-theme |
Your selected colour theme (dark/light) | Persistent |
sidebar-pinned |
Whether the sidebar is pinned open | Persistent |
dm-notes-* |
Your session notes and DM prep | Persistent |
dm-players-* |
Player character data | Persistent |
dm-characters-* |
NPC and creature data | Persistent |
dm-campaigns-* |
Campaign names and settings | Persistent |
dm-maps-* |
Map notes and image URLs | Persistent |
dm-charsheet-* |
Character sheet ability scores and skills | Persistent |
campaign-type-map-* |
Campaign type assignments (campaign vs one-shot) | Persistent |
encounter-* |
Saved encounter builder data | Persistent |
initiative-* |
Saved initiative tracker state | Persistent |
dm-locations-* |
Location data (towns, dungeons, landmarks, NPC assignments) | Persistent |
dm-display-name-* |
Your custom display name | Persistent |
player-campaign-map-* |
Player-to-campaign assignments | Persistent |
char-campaign-map-* |
NPC/creature-to-campaign assignments | Persistent |
dm-cookie-consent |
Whether you accepted or declined the cookie consent banner | Persistent |
spell-slots-* |
Per-player spell slot usage tracking | Persistent |
encounter-templates-* |
Saved encounter template presets | Persistent |
The * represents your unique user ID, so each account's data is kept separate.
Session Storage
Temporary data stored only while your browser tab is open. Cleared automatically when you close the tab.
| Key Pattern | Purpose |
|---|---|
api-cache-* |
Cached API responses from Open5e and dnd5eapi.co (1-hour TTL) to reduce network requests |
sidebar-scroll |
Sidebar scroll position so it stays in place when navigating |
What We Don't Use
- No advertising or marketing cookies
- No analytics cookies (no Google Analytics, Mixpanel, etc.)
- No tracking pixels or web beacons
- No browser fingerprinting
- No third-party social media tracking cookies
- No cross-site tracking of any kind
Managing Cookies and Storage
You can manage or delete cookies and browser storage at any time:
- Browser settings — Most browsers let you view and delete cookies in Settings > Privacy > Cookies. Deleting authentication cookies will sign you out.
- Clear localStorage — In your browser's Developer Tools (F12), go to Application > Local Storage and delete entries starting with
dm-. This will erase your saved campaign data on this device. - Clear sessionStorage — Close the browser tab. All session storage is automatically cleared.
Note: Blocking essential authentication cookies will prevent you from signing in.
Contact
If you have questions about this cookie policy, contact: arany.mak@gmail.com
See also our Privacy Policy for full details on how we handle your data.