Question2Answer 是一个用 PHP 实现的类 StackOverflow 网站的问答系统。

Question2Answer v1.5.3 changelog：

New Features

Added new Snow theme by Q2A Market, selected by default in new installations.

Added loading spinners for all Ajax page actions awaiting a server response (except voting).

Added support for OpenSearch, allowing Q2A sites to be searched directly from browsers and search engines.

Added support for avatars with external user management, including when integrating with WordPress.

Added support for automatic detection and linking of URLs within HTML formatted content.

Bug Fixes

Fixed MySQL error when adding events under external user integration with textual user identifiers.

Fixed incorrect highlighting of custom page links if their path begins with the path of the current page.

Fixed some HTML validation errors by changing HTML tags and ordering.

Fixed occasional PHP notice when viewing an IP address page.

Prevented posts belonging to deleted users from being claimable by other users.

Fixed dual use of the CSS class qa-nav-sub-selected.

Fixed display of names containing a forward slash (/) in the category menu.

Fixed PHP notice displayed if captchas are activated but no captcha module is available.

Prevented the IP address of the approver of a post from being assigned to the post's author.

Fixed auto-complete for tags containing ampersands.

Fixed the number of tags available for auto-complete (now 1,000 by default).

Fixed the 'Delete hidden posts' button leaving behind some hidden questions without dependents.

Fixed MySQL error when indexing a post containing a very long word, if MySQL is in strict mode.

Prevented caret jumping into tags field when asking a question in Internet Explorer.

Fixed momentary expansion of the page header casued by the Facebook Login button.

Fixed censoring of single-character Chinese, Japanese and Korean (CJK) ideographic words.

Question pages which are paginated now include the page number in their canonical URLs.

Other Changes

Added new CSS classes on question or answer lists where all voting is disabled.

Added new CSS class to identify zero answer counts in question lists.

Added new and CSS class to wrap post avatars and meta information.

Updated to CKEditor 3.6.4 and jQuery 1.7.2.

Prevented maximum login rate being set to zero, which could lock administrators out.

Blocked IP addresses can no longer send messages through the feedback form.

Restricted the qa-check-lang.实现 language checking script to administrators only.

Added parameter to qa_sanitize_html() to distinguish between storage and display.