How to make the with-words extending work on regular, automatic completion?

[psprint]

Hi,
I'm using the following snippet in order to make the "completion extended with the words that follows the previous expansion in other contexts", as per README:

imap <expr> <C-A> mucomplete#extend_fwd("\<C-A>")

However, it works only when I start the completion with Tab. Can this feature be also used with the regular, multi-stage – and also automatically (i.e.: always) active completion?

[lifepillar]

It works for me, independent of how the completion menu is triggered. A menu item must be selected, then you may press CTRL-A to extend it.

I don't know what you mean by "regular, multi-stage" completion. Can you provide a more detailed example of how you are expecting it to work?