Cannot add items to "Convert Files" list

[bermudi]

Describe the bug Trying to add file to start conversion to different format but after adding the files the list looks empty and nothing can be converted.

Distro (please complete the following information):

• OS: ArchLinux
• Version n/a

** Info do app (please complete the following information):**

• Version 0.2.4-5
• Instalation repo package

To Reproduce (If applicable) Steps to reproduce the behavior:

1. Click on destination format to start adding files
2. Click the + button to add a file
3. Select a file in nautilus
4. List appears empty instead of listing the file just added
5. Click Start Conversion but nothing happens and no error message

Screenshots (If applicable) Add screenshots to help explain your problem.

Additional context (If applicable)

If I run ciano from the CLI it does output an error message:

** (ciano:89708): CRITICAL **: 13:58:09.593: string_last_index_of: assertion 'self != NULL' failed** (ciano:89708): CRITICAL **: 13:58:09.593: string_substring: assertion 'self != NULL' failed** (ciano:89708): CRITICAL **: 13:58:09.593: string_substring: assertion 'self != NULL' failed