On MW recently upgraded from 1.31 to 1.35 and Structured Discussions Flow-REL1_35-7062bfa, all discussion pages that existed before the upgrade now display error messages instead of discussions content/UI, of which so far two classes pertaining to workflows were identified, described in the following sections.
It is unknown whether the issue persisted from 1.31 or introduced after the upgrade to 1.35.
Creating new discussions works as expected, however.
Error
Pages with the generic title "Error" contain a back trace such as:
[32ac8efaa806b35b147b762f] /wiki/%D8%AE%D8%A7%D8%B5:%D8%AA%D8%BA%D9%8A%D9%8A%D8%B1_%D8%A3%D8%B3%D9%85%D8%A7%D8%A1_%D8%A7%D9%84%D9%85%D8%B3%D8%AA%D8%AE%D8%AF%D9%85%D9%8A%D9%86 Flow\Exception\FlowException from line 77 of /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/BoardMover.php: Could not locate workflow for page ID 4721
Backtrace:
#0 /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/Hooks.php(1723): Flow\BoardMover->move()
#1 /srv/www/genderiyya.xyz/mw/includes/HookContainer/HookContainer.php(329): Flow\Hooks::onTitleMoveStarting()
#2 /srv/www/genderiyya.xyz/mw/includes/HookContainer/HookContainer.php(132): MediaWiki\HookContainer\HookContainer->callLegacyHook()
#3 /srv/www/genderiyya.xyz/mw/includes/HookContainer/HookRunner.php(4010): MediaWiki\HookContainer\HookContainer->run()
#4 /srv/www/genderiyya.xyz/mw/includes/MovePage.php(564): MediaWiki\HookContainer\HookRunner->onTitleMoveStarting()
#5 /srv/www/genderiyya.xyz/mw/includes/MovePage.php(385): MovePage->moveUnsafe()
#6 /srv/app/mediawiki/1.35.5/core/extensions/Renameuser/includes/SpecialRenameuser.php(367): MovePage->move()
#7 /srv/www/genderiyya.xyz/mw/includes/specialpage/SpecialPage.php(600): SpecialRenameuser->execute()
#8 /srv/www/genderiyya.xyz/mw/includes/specialpage/SpecialPageFactory.php(635): SpecialPage->run()
#9 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(307): MediaWiki\SpecialPage\SpecialPageFactory->executePath()
#10 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(945): MediaWiki->performRequest()
#11 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(548): MediaWiki->main()
#12 /srv/www/genderiyya.xyz/mw/index.php(53): MediaWiki->run()
#13 /srv/www/genderiyya.xyz/mw/index.php(46): wfIndexMain()
#14 {main}Unknown discussion
Error pages with this title display a back trace such as:
[4bf928746e88167cce62beef] /mw/index.php?title=%D9%86%D9%82%D8%A7%D8%B4_%D9%88%D8%AB%D9%8A%D9%82%D8%A9:%D8%B1%D8%AF_%D9%87%D8%B4%D8%A7%D9%85_%D8%B9%D9%84%D8%A7%D9%85_%D8%B9%D9%84%D9%89_%D9%86%D8%B4%D8%B1_%D8%B4%D9%87%D8%A7%D8%AF%D8%A9_%D9%85%D8%AC%D9%87%D9%84%D8%A9_%D8%B6%D8%AF_%D8%A7%D9%84%D9%85%D8%AF%D8%B9%D9%88_%D9%87.%D8%B9&topiclist_sortby=newest Flow\Exception\UnknownWorkflowIdException from line 127 of /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/WorkflowLoaderFactory.php: The requested workflow does not exist on this wiki.
Backtrace:
#0 /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/WorkflowLoaderFactory.php(103): Flow\WorkflowLoaderFactory->loadWorkflowById()
#1 /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/Actions/FlowAction.php(99): Flow\WorkflowLoaderFactory->createWorkflowLoader()
#2 /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/Actions/ViewAction.php(26): Flow\Actions\FlowAction->showForAction()
#3 /srv/app/mediawiki/1.35.5/extra/extensions/Flow-REL1_35-7062bfa/includes/Actions/FlowAction.php(49): Flow\Actions\ViewAction->showForAction()
#4 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(532): Flow\Actions\FlowAction->show()
#5 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(313): MediaWiki->performAction()
#6 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(945): MediaWiki->performRequest()
#7 /srv/www/genderiyya.xyz/mw/includes/MediaWiki.php(548): MediaWiki->main()
#8 /srv/www/genderiyya.xyz/mw/index.php(53): MediaWiki->run()
#9 /srv/www/genderiyya.xyz/mw/index.php(46): wfIndexMain()
#10 {main}