Feature request: notes on folder

[rste79]

Hello, I'd like to attach notes to a folder instead of to a specific message. That would be useful to quickly find information relating the contents of the folder (e.g. if a folder contains messages from a customer, the notes could be used to summarize outstanding issues with this customer). These notes should be shown in a panel below the folder tree.

[mlazdans]

Sounds like job for a different extension.