Advanced option "alternate-target-paths" is not present on the UI in some cases

[atestovgit]

• [ x] I have searched open and closed issues for duplicates.

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Environment info

• Duplicati version: 2.0.7.1_beta_2023-05-25
• Operating system: Windows 10 Version 22H2 (Build 19045.3570)
• Backend: local

Description

In some cases the created backup doesn't show added option alternate-target-paths on the web UI when Edit the backup

Steps to reproduce

1. UI Menu "Add backup" -> "Next" button
2. On the General tab:
   • Name: "test backup"
   • Click "Generate" link to generate Passphrase
   • Click "Next" button
3. On the "Destination" tab:
   • Click "Manually type path"
   • Folder path: C:\tmp_dest1\
   • Add Advanced option alternate-target-paths with value C:\tmp_dest2\
   • Click "Next" button
4. On the "Source data" tab:
   • Add any existent source folder with files e.g. C:\tmp_source\
   • Click "Next" button
5. On the "Schedule" tab:
   • Uncheck "Automatically run backups." checkbox
   • Click "Next" button
6. On the "Options" tab:
   • Click "Save" button
7. Click on the created backup "test backup" and then "Edit" link
8. Click "Destination" tab and then "Advanced options"

• Actual result:
  alternate-target-paths option is not present on the UI
• Expected result:
  alternate-target-paths option is present on the UI with C:\tmp_dest2\ value

Screenshots

Notes:

• Although option is not visible on UI, the backup is working as expected.
• Exported json configuration file contains alternate-target-paths with correct value
• When fill destination path with tmp_dest1\ value (instead of C:\tmp_dest1\) during the new backup creation then alternate-target-paths is present on UI as expected
• Although backup is working as expected, after re-saving backup option alternate-target-paths will be lost

[gpatel-fr]

Duplicate of #4553