Why the Canvas Fingerprint Changes

A canvas fingerprint commonly comes from drawing text or shapes, reading the resulting pixels, and calculating a digest. It is not a fixed identifier supplied by the browser. Different drawing inputs, calculation methods, and combined fields can produce different results.

MaskPilot enables Canvas information by default. Each profile keeps its own protection seed and continues using that seed across launches instead of generating a new one on every page refresh. The stable part is the profile-level protection seed. This does not guarantee that every test site will return the same digest forever after a browser upgrade or a change to its test logic.

Changes within the expected boundary

A canvas test result may change when any of the following happens:

1. The test site changes its drawing input, fonts, dimensions, or digest algorithm.
2. The browser version assigned to the profile changes, which may alter the underlying rendering result.
3. A system font, graphics condition, or scaling factor involved in rendering changes.
4. A different profile or a profile copy is launched. Copying creates an independent profile identity and protection seed.
5. Environment randomization identity is edited or regenerated. This replaces the profile’s protection seed and should not be done unless necessary.
6. Canvas information is changed and the comparison spans the sessions before and after a full relaunch.
7. The page reports a combined fingerprint rather than the isolated canvas field.

For these reasons, a “unique” label or a changed digest does not by itself prove that the profile configuration failed. A test site only describes what it observed during that test; it cannot prove how another website correlates visitors in production.

Canvas, WebGL, fonts, and audio are separate surfaces

Canvas information protects canvas readback. WebGL metadata, font information, and audio information have separate controls. Screen size, language, time zone, network exit, cookies, and the website account are also outside the canvas setting.

If a combined fingerprint changes, expand the result and identify whether the canvas field or another field changed. Do not modify several settings at once merely to match an overall score or digest, because doing so removes the reproducible baseline.

WebGL metadata protection is also a separate option and is not enabled together with canvas protection by default. See configure a stable browser fingerprint for the boundary of each setting.

Recommended troubleshooting order

1. Confirm that every launch uses the same MaskPilot profile, and record the current browser version.
2. Fully close the profile and confirm that its browser process has exited.
3. Edit the profile, confirm the Canvas information state under fingerprint settings, and save.
4. Confirm that Environment randomization identity was not edited or Regenerate selected during troubleshooting. There is no need to view, record, or send the value itself.
5. Relaunch the profile and repeat the same page test several times without cleaning the profile, installing extensions, or changing other settings.
6. Compare the isolated canvas field instead of only the “overall fingerprint” or risk score.
7. If the result still changes, record the test page, test time, browser version, and whether a version update, profile copy, regenerated environment identity, or system-font change occurred.
8. Change only one variable, fully relaunch, and test once more to identify the responsible boundary.

Fingerprint settings are read when the browser process starts. Refreshing a page does not apply a saved change. See why profile settings did not apply for the complete lifecycle. When comparing a profile copy, first review the difference between sharing and copying a profile.

Stability does not mean unlinkability

Canvas protection reduces direct exposure of actual rendering characteristics and gives one profile a reproducible protection identity. It does not promise anonymity or prevent correlation. A website can still combine the signed-in account, cookies, IP address, screen, language, time zone, and interaction behavior.

Prefer a reasonable, stable environment for the same profile and purpose instead of trying to make every test result random. Avoid repeatedly adjusting the configuration in response to one test site. If screen fields also differ, continue with why browser screen resolution looks wrong.

Before contacting support

Provide the test page’s domain and exact field, browser version, whether this was the original profile or a copy, whether Environment randomization identity was recently regenerated, the Canvas information state, the retest time after a full relaunch, and a screenshot limited to the relevant fields. Do not provide the environment identity value. Redact website accounts, cookies, tokens, and other personal data.

MDN’s browser fingerprinting overview explains that websites combine features such as browser version, fonts, screen, and settings. The W3C fingerprinting mitigation guidance likewise defines fingerprinting around observable configuration and characteristics that can identify or re-identify a browser, user, or device. An isolated canvas digest should not be interpreted without the other signals.