Function request: Add current page

[Humanen]

I've saved several windows with sets of web-pages, and giving the windows a name - and it all works very well!
What I would like to have is the possibility to easily add a web-page (the current) to a chosen, saved window.
Could be drag and drop, or a sub-menu when rightclicking on the tab, or a button "Update window with current web-pages".
Thanks for your good work.