[Feature request] Collapse / Expand for multipart archives

You know what's boring and clutterly? Multipart archives.

I would like to have a function where I could easily view and execute file operations on a collection of archives at once (an archive group), namely all files in a multipart archive.

Mockup:

(Just a quick mockup based on normal file grouping, it would be nice to see more functionality, like having the total size shown on the group.)

I know that a toggle button with (variants of) this filter would pretty much do the trick, but that would only hide/show all of the archives at once and not just a specific archive group, and it wouldn't support selecting and executing file operations on all the files in a specific archive group at once.

(*.part[2-9].rar|*.part[0-9][2-9].rar|*.part[1-9][0-9].rar)