Release notes on https://github.com/shish/shimmie2/releases should include notes on any major changes

Either one of:

• git checkout branch-2.11 && git pull -- pull the latest stable code
• git checkout main && git pull -- pull the latest in-development code

Once the new Shimmie code is ready, you'll need to make sure all the dependencies are in place and up-to-date via composer install.

• download the new .zip
• extract it
• copy the data folder across from the old install into the new one

This should be automatic - next time the site is loaded, it'll see that the current schema is out of date, and will update it.

• No more support for PHP 8.1
• Removed the half-implemented Hellban system - it didn't work reliably, and it made other things worse - if anybody really wants this, feel free to open a feature request

• Far more extensive configuration system
• Far more extensive permissions system
• Far more extensive CLI interface (php index.php list)
• Several new extensions (bone quality, handle audio, post descriptions, ratings blur, robots.txt, terms & conditions, tombstones)

• Instead of trying to handle all media formats, the default image/video/audio handlers only handle web-standard formats
  • There are new "image++" and "video++" handlers, which will convert to web-standard formats at upload time
  • "Convert format at upload time" behaviour removed from the transcode extensions
• Avatars split out of core, into separate "Gravatar" and "Post Avatars" extensions
• CAPTCHA split out of core, into separate "ReCaptcha" an "Simple Captcha" extensions
• Click-to-zoom split out of core, into separate "Zoom to Fit" and "Zoom to Click" extensions

• Configuration
  • SPEED_HAX system config is removed; the various things it enabled are now part of the regular Board Config settings (Under the "Advanced" option)
  • STATSD_HOST system config is removed, statsd is configured with regular Board Config settings
  • Avatar support is no longer built-in to User, we now have multiple avatar providers to choose from
    • "Gravatar" is the provider used in all versions of Shimmie so far, if you just want to carry on like before, enable this extension
    • Instead, or in addition, there is now an extension to set cropped parts of posts as avatars
    • Both can be enabled at the same time -- if the user has a post avatar, that'll be shown; else if they have an email address configured, a gravatar will be shown; else the avatar slot will be empty
  • CAPTCHA support is now added with extensions (eg, the ReCaptcha extension). If a captcha extension is enabled, then captchas will be added around the site, and specific user classes can skip them based on class permissions.
• Theme development
  • Theme classes should now have a const KEY = "extension_id"; to connect them to the extension with the same ID
  • The Page $page parameter has been dropped from a bunch of theme functions - themes should now consistently use the Ctx::$page global
  • Lots of places switched from string-concatenation to MicroHTML. If you have custom themes, they may need updating - the quick and dirty way is to wrap your HTML strings in \MicroHTML\rawHTML(...)
  • Theme overrides changed from CustomFooTheme to MyThemeFooTheme (eg the danbooru2 override for FooTheme is Danbooru2FooTheme)
  • Common elements (thumbnail, paginator) moved from Themelet to CommonElementsTheme, which can be overridden in the normal way, with MyThemeCommonElementsTheme
  • Each theme's custom Page should now be named MyThemePage and inherit from Page
• Extension Development
  • global variables deprecated in favour of a Context class - for quick compatibility, replace eg global $database; with $database = Ctx::$database
  • Total overhaul of the Board Config / User Config pages
    • Settings should now all be defined in config.php files for each extension
    • $config->get_{int|string|...}() functions replaced with a single $config->get() whose type depends on which config variable is being fetched
  • Major overhaul of the Permission system
    • Permissions should now be defined in permissions.php files for each extension
    • The old gigantic Permissions class got broken into many pieces, eg Permissions::CREATE_COMMENT is now CommentPermission::CREATE_COMMENT
    • Permission IDs (the strings used to uniquely identify a permission) are mostly unchanged
    • (Work in progress) UserClasses and Permissions are stored in the database rather than in user-classes.conf.php
  • Removed global $user_config; and UserConfig::get_for_user($id); -- use $user->get_config(); instead
  • Removed SCORE_LOG_* constants in favour of the Shimmie2\LogLevel enum
  • Extension / ExtensionInfo / etc classes are now grouped by const KEY = "extension_id"; instead of by class name
  • $page->set_redirect($url) now implies mode=REDIRECT; $page->set_data(...) implies mode=DATA, etc - no need to manually call $page->set_mode(...) unless you're doing something weird
• Core development
  • Total re-organisation of files in core/
    • One file per PHP class - it's not quite PSR-4 (the whole app is a single namespace spread across many folders), but it's going in that direction
    • Various random unorganised functions got put into classes, eg is_bot() became Network::is_bot(), log_error() became Log::error()
    • Folders in 2.12 mostly map to files in 2.11 - eg the one giant "search.php" is now several medium-sized files in a "search" folder
    • Test classes live next to their tested classes
  • Load balancing algorithm changed from Flexihash (because that library hasn't been updated in years, and isn't php8.4 compatible) to Weighted Rendezvous Hashing (Which is much simpler, better at balancing, and almost as fast)