trigger completion on /**

The intelephense language server can generate doc blocks with auto completion on /**.

If i use the default neovim lsp omnifunc i get the doc block suggested. Completion-nvim however does not trigger any completion on /**

i tried let g:completion_trigger_character = ['/**'], but it did not make any difference

can i trigger the completion menu manually ? the default omnifunc does not process textEdits ?