Can I get a report of all modified text if I want to analyze, troubleshoot, and diagnose the cause of unexpected action?

No, but you can use the Manage Configurations dialog box to download all your configurations to a .zip file.

To export all your configurations:

1. Click your user image or name in the global header, and on the Settings and Actions menu, select Manage Configurations.
2. On the Manage Configurations dialog box, you can search for the files ending with .xlf or .xml.
3. Click Download Configuration for All Layers.

These files list all text changes done in your application using browser-based tools, such as Application Composer, Page Composer, and User Interface Text. You can use the contents of these files for diagnosis and troubleshooting purposes. However, these files can't be uploaded to the sandbox.