[tor-bugs] #23888 [Obfuscation/Snowflake]: Creating a Snowflake WebExtension addon

[Tor Bug Tracker & Wiki]

#23888: Creating a Snowflake WebExtension addon
-----------------------------------+---------------------------
 Reporter:  oarel                  |          Owner:  arlolra
     Type:  enhancement            |         Status:  assigned
 Priority:  Medium                 |      Milestone:
Component:  Obfuscation/Snowflake  |        Version:
 Severity:  Normal                 |     Resolution:
 Keywords:  ux-team tor-pt         |  Actual Points:
Parent ID:                         |         Points:
 Reviewer:                         |        Sponsor:  Sponsor19
-----------------------------------+---------------------------

Comment (by dcf):

 It looks good so far. I like the refactoring changes. If it makes things
 easier re #27385, I'm fine with merging what's been changed so far.

 I built the WebExtension by running `cake.coffeescript webext` in the
 proxy directory. Then I loaded it into Firefox by going to
 `about:debugging`, clicking "Load Temporary Add-on", and selecting
 manifest.json.

 The browser console (Ctrl+Shift+J) shows a couple of warnings that I don't
 immediately know how to interpret, and also text showing that tmp.js isn't
 working to set the opt-in cookie.
 {{{
 1557301394666
 addons.webextension.280b152ec6e19b8aec7a29eebdd1af8e61a85964 at temporary-
 addon    WARN    Loading extension
 '280b152ec6e19b8aec7a29eebdd1af8e61a85964 at temporary-addon': Reading
 manifest: Error processing background.persistent: Event pages are not
 currently supported. This will run as a persistent background page.
 1557301394692
 addons.webextension.280b152ec6e19b8aec7a29eebdd1af8e61a85964 at temporary-
 addon    WARN    Please specify whether you want browser_style or not in
 your browser_action options.
 Snowflake: == snowflake proxy ==
 Snowflake: Not opted-in. Please click the badge to change options.
 Snowflake: Currently not active.
 }}}

 It works for me in Chromium. I seem to remember that the cookie thing is
 one of the incompatibilities between Firefox and Chromium. I remember
 encountering this problem when I spent a little time trying to hack
 together a WebExtension, but I don't remember if I figured it out or not.
 One thing to try would be [https://developer.mozilla.org/en-
 US/docs/Mozilla/Add-ons/WebExtensions/API/cookies/set#Syntax cookies.set]
 with a `url` from [https://developer.mozilla.org/en-US/docs/Mozilla/Add-
 ons/WebExtensions/API/runtime/getURL runtime.getURL]. Of course, if you're
 planning to refactor the opt-in so that the WebExtension doesn't even need
 a cookie to work, that's better.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23888#comment:17>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online