before Thunderbird update I could send Quickbooks PO with pdf attachment, now it doesn't open a new email screen in Thunderbird.

before Thunderbird update, I could fill in a PO in Quickbooks and 'send email' which opened a new Thunderbird email screen. I would then be able to add a pdf attachment and send through Thunderbird, seeing all the details in the 'sent' folder. Now, QB has asked me to configure 'send forms preferences' for emails - which I've never had to do before -- it's the same QB software I've been running for 4 years. When I write POs now, it opens a QB email screen where I can supposedly add attachments (pdf) but vendors are saying the attachments aren't there. It's double the work to email the PO then send another email with pdf attachments. Plus, where can I find a log of the 'sent emails' in QB?? If it's using Thunderbird to send emails, it is not showing in the sent log. I just want to go back to the old version of Thunderbird where sending an email through QB opened a new 'write email' in thunderbird!