backtrace:
```
{
"file": "/srv/mediawiki/php-On https://mediawiki.org/w/index.php?title=Topic:R017r5i1sq5edfia&action=edit-title&topic_postId=r017r5i1sq5edfia&topic_format=topic-title-wikitext :
```2016-11-02 18:53:06 [WBo2EgpAAD8AAZeMPasAAAAM] mw1268 mediawikiwiki 1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php",
"line": 1102,
"function": "decideNonTopicTitleContentFormat",
"class": "Flow\\Formatter\\RevisionFormatter",
"type": "->",
"args": [
"Flow\\Model\\PostSummary",
"NULL",
"string" exception ERROR: [WBo2EgpAAD8AAZeMPasAAAAM] /w/index.php?title=Topic:R017r5i1sq5edfia&action=edit-title&topic_postId=r017r5i1sq5edfia&topic_format=topic-title-wikitext Flow\Exception\FlowException from line 1159 of /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php: Default format of 'topic-title-html' or 'topic-title-wikitext' can only be used to format topic titles. {"exception_id":"WBo2EgpAAD8AAZeMPasAAAAM"}
[Exception Flow\Exception\FlowException] (/srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php:1159) Default format of 'topic-title-html' or 'topic-title-wikitext' can only be used to format topic titles.
]
},
{#0 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php(1102): Flow\Formatter\RevisionFormatter->decideNonTopicTitleContentFormat(Flow\Model\PostSummary, NULL, string)
"file": "#1 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php",php(266): Flow\Formatter\RevisionFormatter->decideContentFormat(Flow\Model\PostSummary)
"line": 266,#2 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php(284): Flow\Formatter\RevisionFormatter->formatApi(Flow\Formatter\FormatterRow, Flow\View, string)
"function": "decideContentFormat",#3 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Block/Topic.php(679): Flow\Formatter\RevisionFormatter->formatApi(Flow\Formatter\TopicRow, Flow\View)
"class": "#4 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow\\Formatter\\RevisionFormatter",/includes/Block/Topic.php(559): Flow\Block\TopicBlock->renderPostApi(array)
"type": "->",
"args": [
"#5 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow\\Model\\PostSummary"/includes/View.php(193): Flow\Block\TopicBlock->renderApi(array)
]
},
{#6 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/View.php(68): Flow\View->buildApiResponse(Flow\WorkflowLoader, array, string, array)
"file": "#7 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Formatter/RevisionFormatter.php",Actions/Action.php(112): Flow\View->show(Flow\WorkflowLoader, string)
"line": 284,#8 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Actions/Action.php(50): Flow\Actions\FlowAction->showForAction(string)
"function": "formatApi",#9 /srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php(505): Flow\Actions\FlowAction->show()
"class": "Flow\\Formatter\\RevisionFormatter",#10 /srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php(289): MediaWiki->performAction(Article, Title)
"type": "->",#11 /srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php(861): MediaWiki->performRequest()
"args": [
"Flow\\Formatter\\FormatterRow",
"Flow\\View",
"string"#12 /srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php(522): MediaWiki->main()
]
},
{#13 /srv/mediawiki/php-1.29.0-wmf.1/index.php(43): MediaWiki->run()
"file": "#14 /srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/w/index.php(3): includes/Block/Topic.php",(string)
"line": 679,
"function": "formatApi",
"class": "Flow\\Formatter\\RevisionFormatter",
"type": "->",
"args": [
"Flow\\Formatter\\TopicRow",
"Flow\\View"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Block/Topic.php",
"line": 559,
"function": "renderPostApi",
"class": "Flow\\Block\\TopicBlock",
"type": "->",
"args": [
"array"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/View.php",
"line": 193,
"function": "renderApi",
"class": "Flow\\Block\\TopicBlock",
"type": "->",
"args": [
"array"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/View.php",
"line": 68,
"function": "buildApiResponse",
"class": "Flow\\View",
"type": "->",
"args": [
"Flow\\WorkflowLoader",
"array",
"string",
"array"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Actions/Action.php",
"line": 112,
"function": "show",
"class": "Flow\\View",
"type": "->",
"args": [
"Flow\\WorkflowLoader",
"string"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/extensions/Flow/includes/Actions/Action.php",
"line": 50,
"function": "showForAction",
"class": "Flow\\Actions\\FlowAction",
"type": "->",
"args": [
"string"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php",
"line": 505,
"function": "show",
"class": "Flow\\Actions\\FlowAction",
"type": "->",
"args": []
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php",
"line": 289,
"function": "performAction",
"class": "MediaWiki",
"type": "->",
"args": [
"Article",
"Title"
]
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php",
"line": 861,
"function": "performRequest",
"class": "MediaWiki",
"type": "->",
"args": []
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/includes/MediaWiki.php",
"line": 522,
"function": "main",
"class": "MediaWiki",
"type": "->",
"args": []
},
{
"file": "/srv/mediawiki/php-1.29.0-wmf.1/index.php",
"line": 43,
"function": "run",
"class": "MediaWiki",
"type": "->",
"args": []
},
{
"file": "/srv/mediawiki/w/index.php",
"line": 3,
"function": "include",
"args": [
"string"
]
}
```#15 {main}
happens on https://mediawiki.org/w/index.php?title=Topic:R017r5i1sq5edfia&action=edit-title&topic_postId=r017r5i1sq5edfia&topic_format=topic-title-wikitext