User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; cs; rv:1.9.1.6) Gecko/20091201 Firefox/3.5.6 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; cs; rv:1.9.1.5) Gecko/20091204 Lightning/1.0b1 Thunderbird/3.0 When composing a new mail message I use drag&drop to attach existing messages from my mailbox (I don't want to save existing messages from my mailbox as EML files and then attach these EML files). In TB 2 it worked as expected but in TB 3.0 I noticed some problematic behavior: Attachment is created but it is not "Content-Type: message/rfc822" as it used to be, it is "Content-Type: text/html" It is not possible to open such attachment from TB 3.0 (I believe it is because of incorrect content type) and when I instruct TB to use Firefox for opening such "Content-Type: text/html" attachment, it gives error related to unregistered mailbox protocol. Reproducible: Always

Same problem as bug 532779?

(In reply to comment #1) > Same problem as bug 532779? Yes, looks the same, sorry for duplicate.