onSubmit script error: TypeError: Cannot read property 'findTabIndexByID' of nullIssue Users observes onSubmit script error: TypeError: Cannot read property 'findTabIndexByID' of null error message when (s)he tries to save an incident (or any other) form; see screenshot below: ReleaseReported in Paris Patch 2, but potentially can happen in any release.CauseThe possible reason is that the form contains a UI Formatter that is defined in sys_ui_formatter.list. Per Line 4 of Procedure of Create a formatter and add it to a form, the value in Formatter column needs to have .xml extension. It is possible that the formatter used on the form and defined in sys_ui_formatter.list doesn't have xml extension in the name. ResolutionMake sure that the name of the formatter used on the form and defined in Formatter column in sys_ui_formatter.list does have .xml extension.