console.js:288 Warning: Each child in a list should have a unique "key" prop.

Check the render method of PageLayout. See https://fb.me/react-warning-keys for more information.
in WithStyles(ForwardRef(Grid)) (created by PageLayout)
in PageLayout (created by ViewTemplateDetails)
in ViewTemplateDetails (created by Context.Consumer)
in Route (created by RenderRoute)
in Switch (created by RenderRoute)
in Suspense (created by RenderRoute)
in RenderRoute (created by App)
in IntlProvider (created by App)
in div (created by MainLayout)
in PagePermissions (created by MainLayout)
in main (created by MainLayout)
in div (created by MainLayout)
in div (created by MainLayout)
in SubscriptionsProvider (created by MainLayout)
in DatadogProvider (created by MainLayout)
in AppInsightsLogger (created by MainLayout)
in MainLayout (created by App)
in Router (created by BrowserRouter)
in BrowserRouter (created by App)
in ForwardRef (created by AuthProvider)
in AuthProvider (created by App)
in StylesProvider (created by ThemeProvider)
in ThemeProvider (created by ThemeProvider)
in ThemeProvider (created by MainProvider)
in SettingsProvider (created by MainProvider)
in MainProvider (created by App)
in App
in Provider

まず、警告で示されている PageLayout の render メソッドを見つけ、ViewTemplateDetails route で問題を再現します。警告を引き起こしているリストを追跡し、その後、route のレンダリング時にコンソールが空であることを確認します。