Privacy Policy — MB Viewer

MokingBird Oy | Business ID: 3615646-1 | Finland

Last updated: April 2026

Introduction

This Privacy Policy describes how MB Viewer ("the application," "the app") handles your data. MB Viewer is a desktop application developed and distributed by MokingBird Oy.

The short version: MB Viewer collects no data during normal operation. Your files stay on your device. We have no servers receiving your content, no analytics pipeline processing your behavior, and no way to see what you're doing inside the app.

This policy exists to be transparent about the very few data-related events that can occur (like optional update checks), so you understand exactly what the app does and does not do.

For questions, contact us at [email protected].

1. Data We Collect During App Operation

None.

When you use MB Viewer — opening files, editing them, switching themes, dragging tabs between windows — no data is transmitted anywhere. The app operates entirely on your local machine. There is no background process sending usage statistics, no analytics SDK tracking your sessions, and no crash reporter sending error logs to our servers.

Specifically, the following are not collected:

Files you open or edit
File contents, names, or paths
Your usage patterns or session duration
Error logs or crash reports
Hardware or OS information
IP address or location

2. Local Preferences Stored on Your Device

To maintain your settings between sessions, MB Viewer stores the following data locally on your device only:

Theme preferences (light/dark/auto)
Editor theme selections
Window and tab state
Font and zoom preferences

This data never leaves your device. It is stored in a local configuration file and can be deleted by removing the app's configuration directory.

3. Optional Update Checks

MB Viewer may offer an option to check for new versions. If you initiate an update check (or if automatic update checks are enabled in Settings):

The app makes a single HTTPS request to our release server (GitHub Releases)
The request contains: current app version number, your operating system type (e.g., Windows, macOS, Linux)
No personal data is included — no user ID, no IP logging by our systems, no device fingerprinting
The response contains only: latest available version number and release notes

You can disable automatic update checks in Settings. Manual update checks are entirely optional.

4. Files You Open

Every file you open in MB Viewer stays on your device.

TSX/JSX files are transpiled locally using Babel Standalone (bundled inside the app)
Markdown is rendered locally using a bundled renderer
HTML files are displayed in a sandboxed iframe running locally
JSON, CSS, JavaScript, SVG, and images are processed entirely in memory on your machine

No file content is sent to MokingBird servers, cloud services, or any third party as a result of using MB Viewer.

5. No Telemetry, No Analytics

MB Viewer contains no telemetry or analytics components of any kind. If optional diagnostic telemetry is ever introduced in a future version, it will be:

Explicitly documented in this policy and in release notes
Opt-in where required by law
Limited to technical diagnostics only (no behavioral tracking, no file content)

MB Viewer contains no telemetry or analytics components of any kind currently. We do not use:

Google Analytics
Mixpanel, Amplitude, or similar analytics platforms
Sentry or similar crash reporting services
Any other data collection SDK

If you want to know exactly what network requests MB Viewer makes, you can use a network monitor — you will find only update check requests (if enabled) and any external resources loaded by HTML files you open inside the app (which are your files, not ours).

6. Data Sharing

We may use service providers for website hosting, binary distribution, and support communications. These providers receive only the minimum data required for service delivery and are not permitted to use your data for unrelated commercial purposes.

We do not sell personal data.

7. International Transfers

MokingBird Oy is based in Finland, within the EU. Where infrastructure services involve data processing outside the EU/EEA, we apply applicable GDPR safeguards.

8. Third-Party Components

MB Viewer is built using open-source components including Electron, React, Vite, Babel Standalone, and KaTeX. These components are bundled inside the app and do not independently contact external services during normal operation.

When you open an HTML file that references external resources (e.g., fonts from Google Fonts, or scripts from a CDN), those resources are loaded by the file you opened — not by MB Viewer's own systems. This is equivalent to opening that HTML file in any web browser.

9. Website (mbviewer.mokingbird.xyz)

The MB Viewer website uses standard web server logging (Netlify hosting). When you visit the website, standard server logs (IP address, browser type, page visited, timestamp) may be recorded for up to 30 days for security and error monitoring purposes.

We aim to use privacy-friendly, cookieless analytics. If analytics are enabled on the website, they will not track individuals and will not use cookies.

10. Your Rights Under GDPR

As a user in the European Union, you have rights under the General Data Protection Regulation including:

Right of access — Request information about any personal data we hold
Right to erasure — Request deletion of your personal data
Right to object — Object to processing of your data

Since MB Viewer collects no personal data during app operation, most of these rights are satisfied by the app's design. For any privacy requests related to website data or download records, contact [email protected].

11. Children's Privacy

MB Viewer is a general-purpose developer tool. It is not directed at children under 13. We do not knowingly collect personal information from children. Since the app collects no personal data at all, there is no data at risk. Parents who have concerns about their child using MB Viewer may contact us at [email protected].

12. Changes to This Policy

If we update this Privacy Policy, we will update the "Last updated" date at the top and publish the new version on the MB Viewer website. For significant changes, we will note them in the app's release notes.

13. Contact

MokingBird Oy Business ID: 3615646-1 Finland