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Environment info

• Duplicati version: 2.0.6.3_beta_2021-06-17
• Operating system: Linux Ubuntu 22.04
• Backend: SFTP

Description

The --force-local option, according to the documentation, can take an empty string. However, in the web GUI, this does not work. If you add the force-local option in the web GUI and leave the input field blank, then it is automatically filled with the stringtrue, which can be seen by saving, exiting the configuration of the particular backup set and going back in.

Duplicati then throws a warning that the locale true does not exist. Exact error: [Warning-Duplicati.Library.Main.Controller-LocaleChangeError]: Failed to apply 'force-locale' setting. Please try to update .NET-Framework. Exception was: "Culture name true is not supported. Parameter name: name"

In the command line, this is not a problem, an empty string is accepted. Tested with duplicati-cli send-mail --send-mail-to=test@example.net --send-mail-from=test@example.net --send-mail-url=localhost --force-locale="".
(And here entering true as string also throws an error: duplicati-cli send-mail --send-mail-to=test@example.net --send-mail-from=test@example.net --send-mail-url=localhost --force-locale="true" complains: Failed to apply 'force-locale' setting. Please try to update .NET-Framework. Exception was: "Culture name true is not supported.)

Steps to reproduce

1. Make a backup set in the GUI
2. set the force-locale option to blank string
3. save, close and re-open the config page of that backup
4. see that the blank field was filled with true
5. run the backup
6. warning that true is not a valid locale appears

• Actual result:
  Option automatically set to true.
  Backup throws warning
• Expected result:
  Option should remain blank.
  Backup should complete without warning.

Other Resources

According to issue #4176, the force-locale setting does not work at all anyways.