Make sure the User Timing API does not provide a new high resolution timestamp

We should make sure that the User Timing API provides timestamps with reduced precision only. See: https://bugzilla.mozilla.org/show_bug.cgi?id=782751 for its implementation.

added MikePerry201506 component::applications/tor browser ff38-esr owner::tbb-team priority::medium resolution::fixed status::closed tbb-fingerprinting-time-highres tbb-pref type::task labels

Trac:
Description: We should make sure that the User Timing API provides timestamps with reduced precision only. See: https://bugzilla.mozilla.org/show_bug.cgi?id=782751 for its implementation

to

We should make sure that the User Timing API provides timestamps with reduced precision only. See: https://bugzilla.mozilla.org/show_bug.cgi?id=782751 for its implementation.

In fact this is a DOMHighresTimeStamp. Units are milliseconds, but resolution is at least microseconds (and even higher resolution for Mozilla Firefox, depending on CPU model).

This API also allows content to store names for timers and timestamps (in what scope? who knows.. the privacy section of the W3C spec basically just takes a shit on any privacy concerns), complicates things like #16110 (moved), and the API generally appears to be useless from a practical point of view.

I say we disable it for now, and maybe even forever. The dom.enable_user_timing pref does in fact seem to work.

Trac:
Keywords: N/A deleted, MikePerry201506, tbb-pref added

I disabled this API via the pref for 5.0a3.

Trac:
Resolution: N/A to fixed
Status: new to closed

closed

mentioned in issue #18597 (moved)

mentioned in issue #18601 (moved)

mentioned in issue #26598 (moved)

mentioned in issue tpo/applications/tor-browser-bundle-testsuite#18597 (closed)

moved to tpo/applications/tor-browser#16336 (closed)

mentioned in issue tpo/applications/tor-browser#26598 (closed)