After upgrade Plesk Onyx to Obsidian, folders with special characters are not displayed properly in Roundcube webmail.
For example, before upgrade a folder appeared in Roundcube as "Entwürfe".
After upgrade folder appears in Roundcube as "Entw&APw-rfe".
IMAP folders with Umlauts (ä, ö, ü) in name disappeared from Thunderbird after upgrade to Obsidian.
This is Plesk bug with ID PPPM-11200, which is planned to be fixed in one of the future product updates.
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