Nested paragraphs are not saving content on already translated nodes.
1) Create a page and add some paragraphs.
2) Translate the page into another language and save it.
3) Add a new paragraph with a sub-paragraph and save it.
4) Visit the translated page and use the contextual link to edit the sub-paragraph.
5) Edit the sub-paragraph content and save it. You'll see the translated page, but the sub-paragraph content is not translated.
In the edit view, the sub-paragraph content is translated, but it does not appear on the frontend.
The issue seems to be related to the parent paragraph, which doesn't have a translation yet when the child translation is saved. In fact, the issue does not occur if the paragraphs are not nested.
Active
3.0
Code
I've added a control that skip contextual links if the current paragraph's parent hasn't a translation in the current language.
A patch is attached.