Mid-measure braces, e.g. for organ stop changes

Disclaimer: I am not an organist, so there might be a more up-to-date way of denoting this.

I'd love the ability to add curly braces mid-measure, across a selection of notes. For example:

Note that the brace spans multiple staves within a system, but does not necessarily cover all the notes.

See this stackexchange discussion for some other examples: https://music.stackexchange.com/questions/117490/unknown-notation-brace…

If there's a workaround to get something working now I'd appreciate it as well.