[BUG] Structure board renders placeholders of wrong language

[fsbraun]

Description

The structure board renders the placeholders of the toolbar's language instead of the object's (i.e. page content's) language.

Steps to reproduce

Steps to reproduce the behavior:

1. Create a new page in English only
2. Add some plugins
3. Change the toolbar language to some other language in the user preferences
4. The content is shown correctly
5. but the structure board is empty

Expected behaviour

The structure board should show the plugins of the content object's language in the toolbar's localization.

Actual behaviour

It shows the plugin tree of the object in the toolbar's language. This is empty for objects that have separate instances per language, such as page content.

Screenshots

Additional information (CMS/Python/Django versions)

Do you want to help fix this issue?

• Yes, I want to help fix this issue and I will join #workgroup-pr-review on Slack to confirm with the community that a PR is welcome.
• No, I only want to report the issue.