Hi I'm new in the forum and this is my first post ...
I've try your solution but the maildir file is not updated and the quota occupation still 0%.
I've read the exim documentation ad I find in this page
this parameter : maildir_use_size_file;
I've insert in the virtual_localdirectory section with value: true.
I've insert the previous configuration in /etc/dovecot.conf to enable quota plugin.
I've restarted exim and dovecot, I sent an email to an user and the file maildirsize was created and in the roundcube the quota level in correctly displayed.
I've make some test to check that's the email system work correcly.
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