Use the latest Google Chrome browser for V5 Mimics!

The V5 mimics require a standard web browser feature called Shared Memory and Atomics.  Currently only the Chrome web browser, version 68 or later, supports this feature by default.  And therefore we recommend using the latest Google Chrome web browser.


Shared Memory and Atomics

Shared Memory and Atomics are features which allow fast transferring of data between the main webpage and Web Workers.  We use workers in the V5 mimics for running the user's program and simulating the physics environment of the robot.

The Shared Memory and Atomics feature was merged into the EMCAScript specification in February 2017 and most browsers released support during 2017 including Chrome, FireFox and Edge.  However when the Spectre and Meltdown timing attacks were reported in January 2018, all of the browsers disabled the Shared Memory feature by default because it was possible to use shared memory to create a very high-resolution timer to exploit these attacks.

Google Chrome has been working on a security feature called Site Isolation for several years.  When Site Isolation is turned on (it is by default in Chrome 68) together with a computer which is up to date with all operating system and manufacturer updates the timing attacks are now mitigated.  And so in Chrome version 68, Google turned on Shared Memory by default.  See the Google Security Blog for more details.

Therefore we recommend using the latest Google Chrome web browser.

Do not manually turn on Shared Memory in other browsers until they have finished corresponding security work.