Hi,
last days I changed my mail program on Mac to Thunderbird and set Thunderbird as custom mail program. If I want to send a pdf document in Devonthink via right mouse click, this opens a mail window of Thunderbird. But instead of pasting the pdf there are only some lines of citation from the content of this pdf file, but not the file. This makes no sense.
In Apple Mail this wirks perfectly. Where can I change this?
Mac M2 Pro Ventura 13.6.5
Thunderbird 115.8.1 (actual)
There is nothing to change in this situation, other than your email app 
You can’t expect the same behavior from every application and Thunderbird is a poor choice if inter-application communication is needed. See this slide in the Help > Tutorials > Handling Emails tutorial…
Note you should be able to drag and drop an email into a draft in Thunderbird.
Update:
Thunderbird’s dock icon does not supporting receiving items via drag and drop.
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