minor #7875 Explain how to provide a stack trace (greg0ire, javiereguiluz)

This PR was merged into the 2.7 branch.

Discussion
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Explain how to provide a stack trace

I miss a reference explaining how to do that properly and keep asking people to do it, so maybe here is the right place?

Commits
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1648c6f Minor fix
6d3ecc9 Minor changes
2972d23 Explain how to provide a stack trace
83f5e1d Add link to the Slack support channel

Author: xabbuh

contributing/code/bugs.rst

@@ -14,8 +14,9 @@ Before submitting a bug:
 * Double-check the official :doc:`documentation </index>` to see if you're not misusing the
   framework;
 
-* Ask for assistance on `Stack Overflow`_ or on the #symfony `IRC channel`_
-  if you're not sure if your issue is really a bug.
+* Ask for assistance on `Stack Overflow`_, on the #support channel of
+  `the Symfony Slack`_, or on the #symfony `IRC channel`_ if you're not sure if
+  your issue is really a bug.
 
 If your problem definitely looks like a bug, report it using the official bug
 `tracker`_ and follow some basic rules:
@@ -32,9 +33,20 @@ If your problem definitely looks like a bug, report it using the official bug
 * Give as much detail as possible about your environment (OS, PHP version,
   Symfony version, enabled extensions, ...);
 
+* If you want to provide a stack trace you got on an HTML page, be sure to
+  provide the plain text version, which should appear at the bottom of the
+  page. *Do not* provide it as a screenshot, since search engines will not be
+  able to index the text inside them. Same goes for errors encountered in a
+  terminal, do not take a screenshot, but copy/paste the contents. If
+  the stack trace is long, consider enclosing it in a `<details> HTML tag`_.
+  **Be wary that stack traces may contain sensitive information, and if it is
+  the case, be sure to redact them prior to posting your stack trace.**
+
 * *(optional)* Attach a :doc:`patch <patches>`.
 
 .. _`Stack Overflow`: http://stackoverflow.com/questions/tagged/symfony2
 .. _IRC channel: https://symfony.com/irc
+.. _the Symfony Slack: https://symfony.com/slack-invite
 .. _tracker: https://github.com/symfony/symfony/issues
 .. _Symfony Standard Edition: https://github.com/symfony/symfony-standard/
+.. _<details> HTML tag: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/details