fix(urlParams): empty save param issue

[jadh4v]

Fix the following error when urlParams are empty.

App.vue:206 Uncaught TypeError: Cannot read properties of undefined (reading 'toString')
    at setup (App.vue:206:54)
    at callWithErrorHandling (chunk-G4DFXOZZ.js?v=fae193fd:1565:18)
    at setupStatefulComponent (chunk-G4DFXOZZ.js?v=fae193fd:8631:25)
    at setupComponent (chunk-G4DFXOZZ.js?v=fae193fd:8592:36)
    at mountComponent (chunk-G4DFXOZZ.js?v=fae193fd:6997:7)
    at processComponent (chunk-G4DFXOZZ.js?v=fae193fd:6963:9)
    at patch (chunk-G4DFXOZZ.js?v=fae193fd:6436:11)
    at render2 (chunk-G4DFXOZZ.js?v=fae193fd:7730:7)
    at mount (chunk-G4DFXOZZ.js?v=fae193fd:5215:13)
    at app.mount (chunk-G4DFXOZZ.js?v=fae193fd:10537:19)

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