I know I can use ibuffer to filter available buffers by mode, but I can I do something analogous directly in helm? The mode is listed by helm, so maybe there is a way?
helm-mini states in its help (which can be accessed with
C-c ? while it's running) that a token prefixed with
* is interpreted as substring match of a major mode. Therefore, entering
*org gives you
org-mode buffers, entering further space-separated tokens can be used to narrow those down even more.