Idea from T34603: search around MediaWiki for "remove after 1.XX release" code and similar and kill that code (or file bugs to remember to remove the code later).
Make sure you use a commit summary that explains what you're doing/removing (reusing this task title isn't a good one!), and also add an entry to RELEASE-NOTES-1.29 similar to those that exist already https://github.com/wikimedia/mediawiki/blob/2c74b04/RELEASE-NOTES-1.29#L54-L68
Example: https://www.mediawiki.org/wiki/Special:Code/MediaWiki/104318 added "Do not release 1.19 with this." in a comment. Search for phrases like that.
List of things that could be removed (thanks to @Matthewrbowker):
Remove after...
<None found>
Deprecated, use ... instead
- class ResetUserTokens
- Skin::doEditSectionLink()
- User::getImplicitGroups()
@deprecated (Soft deprecated)
- class ProfileSection
- function wfProfileIn() (ProfilerFunctions.php)
- function wfProfileOut() (ProfilerFunctions.php)
- class SpecialResetTokens
- EDIT_TOKEN_SUFFIX (in User.php)
User::randomPassword()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/505342)User::setPassword()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/609485)User::setInternalPassword()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/607766)User::setNewpassword()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/536656)- User::getTokenFromOption()
- User::setCookie()
- User::clearCookie()
- User::setExtendedLoginCookie()
User::checkPassword()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/596716)User::checkTemporaryPassword()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/596711)User::getEditTokenTimestamp()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/423180)User::addNewUserLogEntry()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/626905)User::addNewUserLogEntryAutoCreate()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/561395)BufferingStatsdDataFactory::getBuffer()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/512288)User::getPasswordFactory()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/423180)User::passwordChangeInputAttribs()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/423180)- Language::initEncoding()
- Language::recodeForEdit()
- Language::recodeInput()
- Interwiki::isValidInterwiki()
- Interwiki::fetch()
- Inetwiki::getAllPrefixes()
- class AuthManagerAuthPlugin
- Class AuthManagerAuthPluginUser
- Status::getErrorsArray()
- Status::getWarningsArray()
- $mUniqPrefix (in class Parser)
- Parser::getRandomString()
- Parser::uniqPrefix()
- Parser::disableCache()
SkinFactory::getDefaultInstance()(https://gerrit.wikimedia.org/r/c/mediawiki/core/+/518325)- ApiQueryInfo::getTokenFunctions()
- ApiQueryInfo::resetTokenCache()
- ApiQueryInfo::getEditToken()
- ApiQueryInfo::getDeleteToken()
- ApiQueryInfo::getProtectToken()
- ApiQueryInfo::getMoveToken()
- ApiQueryInfo::getBlockToken()
- ApiQueryInfo::getUnblockToken()
- ApiQueryInfo::getEmailToken()
- ApiQueryInfo::getImportToken()
- ApiQueryInfo::getWatchToken()
- ApiQueryInfo::getOptionsToken()
- LoadBalancer::getLaggedSlaveMode()
- LoadBalancer::laggedSlaveUsed()
- MimeMagic::singleton()
- class ApiTokens
wfDeprecated (Hard deprecated)
Parser::getRandomString()(rMW1a2ef297eb17)Parser::uniqPrefix()(rMW1a2ef297eb17)$uniq_prefix in Parser::extractTagsAndParams()(rMW1a2ef297eb17)ApiQueryLogEvents::addLogParams()(rMW6ff65e57bbf2)- In DifferenceEngine::textDiff() there is a notation deprecating a variable
- $wgSessionsInObjectCache in class Setup
- SearchEngine::getOpenSearchTemplate()
WikiImproter::__construct() without a Config instance(rMWaf1434ff2fea)- LoginSignupSpecialPage::getFakeTemplate() has hook references depricated
ChangeTags::listExtensionActivatedTags()(rMW390f6411e09b)ChangeTags::listExtensionDefinedTags()(rMW390f6411e09b)VFormHTMLForm::isVForm()(rMWae7237ea9839)User::setCookie()(rMW5ab3ae037114)User::clearCookie()(rMW5ab3ae037114)User::setExtendedLoginCookie()(rMW5ab3ae037114)ApiPageSet::getInvalidTitles()(rMW6ff65e57bbf2)- User::createNew()
User::getEditTokenTimestamp()(rMWc8ea95160ae0)User::getPasswordFactory()(rMWc8ea95160ae0)Revision::getRawUser()(rMW318706a27c52)Revision::getRawUserText()(rMW318706a27c52)Revision::getRawComment()(rMW318706a27c52)- MWLBFactory::getLBFactoryClass() (inside the class)
- Class LoginForm
- Job::batchInsert()
UploadBase::stashFileGetKey()(rMWe745bfed82c4)UploadBase::stashSession()(rMWe745bfed82c4)- MWExceptionHandler::getLogId()
- ApiResult::__construct - handing instance of ApiMain
ApiBase::getModuleProfileName()(rMW80f787fba3e8)ApiBase::safeProfileOut()(rMW6ff65e57bbf2)ApiBase::getProfileTime()(rMW64b146e55a13)ApiBase::profileDBIn()(rMW6ff65e57bbf2)ApiBase::profileDBOut()(rMW6ff65e57bbf2)ApiBase::getProfileDBTime()(rMW3f1230e9ec36)- ResourceLoader::readStyleFiles() without a ResourceLoader context.
- SpecialPageFactory::getList()
- SpecialPageFactory::getPage() - Array syntax
- StripState::__construct called with any arguements
- GlobalFunctions.php - wfErrorLog()
- GlobalFuctions.php - wfFixSessionID()
- GlobalFunctions.php - wfResetSessionID()
- GlobalFunctions.php - wfSetupSession()
Linker::getLinkColour()(rMW03e7ae45bcb1)- Linker::link() with $query as string
- SkinTemplate::outputPage() (Not sure on this one, it's hidden in an if())
Linker::formatTemplates()(rMW8d47f5368785)- MailAddress::__construct() called with a user object
- Block::__construct with multiple arguements
OutputPage::__construct with no context(rMWc4145b2f087c)OutputPage::addExtensionStyle()(Unknown Commit)OutputPage::getExtStyle()(Unknown Commit)HTMLForm::isVForm()(rMWae7237ea9839)