[Closed] documentation of xml configuration

Background of the issue:
I am trying to translate several sections of my u-design theme using XML configuration. I found documentation related to this process.

Symptoms:
I need confirmation if the documentation I found is correct and if it is from WPML.

Questions:
Can you confirm that the documentation I found about XML configuration for translating the u-design theme is correct?
Is the documentation from WPML?
https://wpml.org/errata/u-design-theme-blocks-and-widgets-not-translatable/