Auto-anchor attribute regexes, document _validTags
FIX: Use lang- prefixes for HLJS; add nohighlight for ...

text; use a proper whiteListTag() call.

Old posts are not affected - no global rebake is necessary.
Clean up validateAttribute() function

Remove code duplication
FEATURE: Allow explicit rel="nofollow" on links
Fix JSHint
Fix data-* behavior (failure to understand own docs)
Update Markdown tests
Add emoji pl_PL localization
Remove href attribute from tab link to prevent duplicate event on enter.

Because Discourse doesn't preventDefault on links with an href of "#"
this tab-able link was firing a click event when enter was pressed. This
had the unfortunate side effect of breaking the history, making routing
and navigation unreliable.
Add additional fields that indicate reply

When scanning for where a reply starts, three lines in a row matching common email reply headers indicate the start of a reply. Add 'Cc', 'Bcc', and 'Date' because these are also common.
Show dismiss posts/topics buttons on category filtered lists
FIX: Make shortcut 'c' global for creating a topic

https://meta.discourse.org/t/keyboard-shortcut-c-create-a-new-topic-does-not-work-globally/18975
Apply comments from eviltrout, using this.get('category.id'), and use snake case for category_id
Call open directly to avoid deprecation warning
BUG: phpBB lists not properly converted

bbcode-to-md happily ignores all phpBB's lists. The list syntax is
    [list][*]item 1
    [*]item 2
    [/list]
and 
    [list=1][*]item 1
    [*]item 2
    [/list]
respectively for [ul] and [ol]s. Luckily, phpBB adds closing tags for [*] items. My workaround simply converts phpBBs lists into bbcode using [ul] and [ol] which then can be converted by the standard bbcode-to-md code.
fixing the broken groups page
Max out summary filter at 100 posts.
Use a site setting for maximum summary results
fixing the broken groups page
FIX: letter avatars were not getting stripped from short emails