Merge remote-tracking branch 'upstream/master' into pipeline-emails

* upstream/master: (237 commits)
  Grapify boards API
  Add test, fix merge error
  Use local assigns to get the dropdown title
  Updated issuable dropdown titles
  Added safety check for formatted values
  Minor style improvement
  Fixed conflict and corrected teaspoon test
  Rename method in test
  Moved ci_status environments logic to new action ci_envrionments_status and set up frontend polling
  Refactor ci_status on MergeRequestController
  Fix indenting error in HAML
  Show what time ago a MR was deployed
  Fixed missing links
  Fixed missing links
  Refactor merge requests revisions
  Add link to update docs for source installations
  Grapify todos API
  Link to review apps example from docs
  fix grafana_configuration.md move link
  Do not run before_script, artifacts, cache in trigger_docs job
  ...

2 files changed, 34 insertions, 0 deletions

diff --git a/doc/development/doc_styleguide.md b/doc/development/doc_styleguide.md
index 39b801f761d..0b725cf200c 100644
--- a/doc/development/doc_styleguide.md
+++ b/doc/development/doc_styleguide.md
@@ -314,6 +314,29 @@ In this case:
 - different highlighting languages are used for each config in the code block
 - the [references](#references) guide is used for reconfigure/restart
 
+## Fake tokens
+
+There may be times where a token is needed to demonstrate an API call using
+cURL or a secret variable used in CI. It is strongly advised not to use real
+tokens in documentation even if the probability of a token being exploited is
+low.
+
+You can use the following fake tokens as examples.
+
+|     **Token type**    |           **Token value**         |
+| --------------------- | --------------------------------- |
+| Private user token    | `9koXpg98eAheJpvBs5tK`            |
+| Personal access token | `n671WNGecHugsdEDPsyo`            |
+| Application ID        | `2fcb195768c39e9a94cec2c2e32c59c0aad7a3365c10892e8116b5d83d4096b6` |
+| Application secret    | `04f294d1eaca42b8692017b426d53bbc8fe75f827734f0260710b83a556082df` |
+| Secret CI variable    | `Li8j-mLUVA3eZYjPfd_H`            |
+| Specific Runner token | `yrnZW46BrtBFqM7xDzE7dddd`        |
+| Shared Runner token   | `6Vk7ZsosqQyfreAxXTZr`            |
+| Trigger token         | `be20d8dcc028677c931e04f3871a9b`  |
+| Webhook secret token  | `6XhDroRcYPM5by_h-HLY`            |
+| Health check token    | `Tu7BgjR9qeZTEyRzGG2P`            |
+| Request profile token | `7VgpS4Ax5utVD2esNstz`            |
+
 ## API
 
 Here is a list of must-have items. Use them in the exact order that appears
diff --git a/doc/development/frontend.md b/doc/development/frontend.md
index f879cd57e25..56c8516508e 100644
--- a/doc/development/frontend.md
+++ b/doc/development/frontend.md
@@ -223,3 +223,14 @@ For our currently-supported browsers, see our [requirements][requirements].
 [xss]: https://en.wikipedia.org/wiki/Cross-site_scripting
 [scss-style-guide]: scss_styleguide.md
 [requirements]: ../install/requirements.md#supported-web-browsers
+
+## Common Errors
+
+### Rspec (Capybara/Poltergeist) chokes on general JavaScript errors
+
+If you see very generic JavaScript errors (e.g. `jQuery is undefined`) being thrown in tests, but
+can't reproduce them manually, you may have included `ES6`-style JavaScript in files that don't
+have the `.js.es6` file extension. Either use ES5-friendly JavaScript or rename the file you're
+working in (`git mv <file>.js> <file.js.es6>`).
+
+