textDocument/documentSymbol is not sent until document is reopened

When I open the first document in a project, no textDocument/documentSymbol request is sent to my language server, and no Outline is available.

If I just close the document and open it again (by double clicking at the file under "Other files" in the Projects field), Qt Creator do send a textDocument/documentSymbol request and successfully populates its Outline field with the information from my language server.

Se the log for details.