i'm using: Thunderbird 128.5.2esr (64-bit) Kubuntu 24.04 KDE Plasma 5.115.0 Qt 5.15.13 when i get attached files, like .jpg, .png, or .pdf, i can see that the message has an attached file, but thunderbird no longer opens those files, or knows how to make other applications, like okular, gwenview, or inkscape open them. this USED TO BE a standard feature. 1. receive an attached file: FILE-NAME.pdf at the bottom of the window is a bar that says "1 attachment: FILE-NAME.pdf 3.8 kB" 2. click on FILE-NAME.pdf EXPECTED RESULT: FILE-NAME.pdf opens in okular ACTUAL RESULT: nothing 3. alternate-click on FILE-NAME.pdf and choose "Open" from the context menu EXPECTED RESULT: FILE-NAME.pdf opens in okular ACTUAL RESULT: nothing 4. alternate-click on FILE-NAME.pdf and choose "Save as..." from the context menu, and save the file somewhere obvious. 5. navigate to somewhere obvious, and open the file RESULT: FILE-NAME.pdf opens i looked at "Settings -> General -> Files & Attachments" and confirmed that "Portable Document Format (PDF)" is set to "Use okular". i also deleted, and re-added "Portable Document Format (PDF)" from "Settings -> General -> Files & Attachments" with no change in the above reported behaviour.