In the past, I have been able to save emails as PDF's using these steps: You first need to select the Message in the Thunderbird application panel. After that, 1. You only need to click on File Menu, 2. and then click on Save selected message. The arrow button will display several file formats. 3. Choose only Save as PDF (Adobe) from it. 4. Then, It will ask for its location to save the message. 5. Choose the destination location, and your Thunderbird email will be saved as PDF file. Instead of saving the file (which I've done many times in the past), I get the attached message. Any ideas for a workaround? I'm using TB 60.7.2 on a relatively new Macbook Air running Mac OS Mojave 10.14.5. Thanks for your help.