detectIncognito

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What detectIncognito actually does

Detects private-browsing mode across engines by probing the storage quota and filesystem behaviours each browser changes when it is in that mode — a narrow surface, maintained properly.

What detectIncognito's maintenance signals mean

The liveness field here is pushed_at, read as 2026-08-09 against a field check 5 days later. That is inside 90 days, and 90 days is where the second edition of the rubric put ACTIVE after moving it down from the first edition's 180.

The reason for the move is worth stating, because it is the kind of threshold that looks arbitrary until you know what it is measuring against: detection changes on a shorter cycle than half a year, so a six-month-old evasion is not a current one. What a recent push does not tell you is what was in it. A commit landing on a branch is not a release, not a fix, and not a test — it is evidence that somebody is still there.

No release was captured for this entry, which this register records as unknown rather than as none. The distinction matters more than it looks: a project with no tags and a project whose tags the sweep failed to read produce the same blank cell, and printing them as the same fact would be the register asserting something it has not measured.

Where detectIncognito sits in this catalogue

detectIncognito is filed in section 06, fingerprinting libraries, whose scope is this: The collectors themselves — the code that reads a browser. Read these to know what is being asked of you. An entry sits in exactly one section here. Where a project could defensibly go in two, it is placed where a reader would look for it first rather than where it fits most tidily, and that is an editorial decision rather than a measured one.

Filed beside it in the same section: ClientJS (DEAD), CreepJS (source) (ACTIVE), Broprint.js (SEMI). Comparing an entry against its own section-mates is more informative than comparing it against the catalogue as a whole, because everything in a section is answering roughly the same question and the differences left over are the ones that matter.

It is published under MIT, alongside the rest of the MIT entries in this register, and it sits with everything else currently marked ACTIVE. Read those two facets together: a permissively licensed project that stopped shipping is not a safer dependency than a copyleft one that did not, and a filter on one axis alone will tell you the wrong thing.

What to settle before you adopt detectIncognito

Techniques here break with every browser release that adjusts a quota, so the push date is unusually load-bearing for a library this small. Read which engines the current version claims to cover.