Best way to archive mails into nextcloud folders

I would like to be able to keep some mails into the nextcloud folder structure, with other documents related to the same project.
It would be great to do that directly from the imap client (Outlook, Thunderbird, webmail…), drag’n’dropping the entire mail (content + attachments) into a folder and it goes to nextcloud.

The eml viewer app is useful to show content of the mail, but I’m looking for a simple method to sync imap folder structure and nextcloud folder structure or a hint to make the move imap->nextcloud easier for all users.
I’m about to build a script myself to sync imap directories with nextcloud, but it’s painful and maybe not the good choice.

The Mail app is unusable for large mailboxes and doesn’t offer this functionality, so it’s not an option…

What do you think about that ?

Most desktop email clients are able to drag and drop emails to the file manager of the OS they are running on. You could then sync those eml files to your Nextcloud by using the Nextcloud Desktop Client.

This would only make sense imho, if you want to backup all emails of an IMAP account as eml files to your Nextcloud, although there are better solutions for email backup. If you only want to store a selection of emails together with related documents in a specific folder, there is probably not an easy way to automate this.

You could open a feature request on GitHub.

Thanks for your advises.
Syncing shared folders and files with many users’ OS expose us to the risk of conflict and file locking. We would like to avoid that.
And it doesn’t work fine from a webmail (we use Snappy Mail under Nextcloud here)

Well I don’t use Snappy Mail (tested the Rainloop integartion years ago), but I asume beside authentication there is still not much direct integration with Nextcloud. I also cannot speak for Nextcloud Mail, since I don’t use it either. You on the other hand seem to know pretty well what features are available in both apps. So if a feature you need isn’t available, you don’t have much of a choice but to open a feature request and hope that it will be implemented at some point in time.

At this point, the desktop client is probably the easiest option. Or you could connect Nextcloud as a network drive (WebDAV) to your computer and then upload the eml files through that. Uploading them via browser is of course also possible.