If someone is re-working this - I am currently enjoying renaming .jpg files in the tmp directory to match what files suggests they are so it doesnt choke trying to import them:
2020-11-13 17:15:02: "Error: Image is invalid or does not exist: /tmp/Nrdmvg7e_6tyD5bab-EplW_l.jpg
Error: Image is invalid or does not exist: /tmp/Nrdmvg7e_6tyD5bab-EplW_l.jpg
at handleResizeImage_ (/tmp/.mount_JoplinCHyX4H/resources/app.asar/lib/shim-init-node.js:121:31)
at Object.shim.createResourceFromPath (/tmp/.mount_JoplinCHyX4H/resources/app.asar/lib/shim-init-node.js:225:21)"
It is nice to know someone is checking the attachments : )
[user@thinkpad src]$ file /tmp/Nrdmvg7e_6tyD5bab-EplW_l.jpg
/tmp/Nrdmvg7e_6tyD5bab-EplW_l.jpg: SVG Scalable Vector Graphics image
These mostly seem to be emoticons. What is wrong with ASCII I ask you?! 
copy paste generic for now. Thanks again