{"record":{"id":"db8042dfcdbdbe0b","repo":"octobercms/october","slug":"missing-a-valid-tab-definition","errorCode":null,"errorMessage":"Missing a valid tab definition.","messagePattern":"Missing a valid tab definition\\.","errorType":"exception","errorClass":"SystemException","httpStatus":null,"severity":"error","filePath":"modules/backend/widgets/Form.php","lineNumber":568,"sourceCode":"            if (!is_array($eventResult)) {\n                continue;\n            }\n\n            $result = $eventResult + $result;\n        }\n\n        return $result;\n    }\n\n    /**\n     * onLazyLoadTab renders all fields of a tab in the target tab pane\n     */\n    public function onLazyLoadTab()\n    {\n        $target  = post('target');\n\n        if (!$tabName = post('name')) {\n            throw new SystemException(Lang::get('backend::lang.form.missing_tab'));\n        }\n\n        $tab = $this->getTab(post('section', 'primary'));\n\n        $fields = $tab !== null ? array_get($tab->getFields(), $tabName) : [];\n\n        return [\n            $target => $this->makePartial('form_fields', ['fields' => $fields]),\n        ];\n    }\n\n    /**\n     * defineFormFields creates a flat array of form fields from the configuration\n     * and slots fields in to their respective tabs\n     */\n    protected function defineFormFields()\n    {\n        if ($this->fieldsDefined) {","sourceCodeStart":550,"sourceCodeEnd":586,"githubUrl":"https://github.com/octobercms/october/blob/b608633a7e8922487d91a8161499020121c3b3bf/modules/backend/widgets/Form.php#L550-L586","documentation":"Error \"Missing a valid tab definition.\" thrown in octobercms/october.","triggerScenarios":"Thrown at modules/backend/widgets/Form.php:568 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"b608633a7e8922487d91a8161499020121c3b3bf","analyzedAt":"2026-08-21T04:24:57.515Z","schemaVersion":2},"datasetVersion":"2026-08-21T11:28:35.574Z"}