How to export the event log from the Console.app into a text file?
You can send the logs as a plane text via mail.
Just press Cmd-Shift-T in Mail.app before sending e-mail (or choose Menu -&gt; Format -&gt; Make Plane Text).
This will clear all formatting in hole email and the recipient will receive the logs in proper format.

Cmd-A, Cmd-C in Console.app and Cmd-V in an empty text file as it was suggested by Seamus.

You can use Terminal.app and directly database were all the logs resides and even do not open Console.app



To see the logs for your app:


log show --predicate 'sender == &quot;the_name_of_your_app&quot;' --style compact



To see the logs for the specified time interval:


log show --predicate 'sender == &quot;the_name_of_your_app&quot;' --style compact --start '2020-10-07 16:55:00' --end '2020-10-07 16:59:00'



To save the logs for the specified time interval into a file to keep/send:


log show --predicate 'sender == &quot;the_name_of_your_app&quot;' --style compact --start '2020-10-07 16:55:00' --end '2020-10-07 16:59:00' &gt; your_library.log



To see the logs in real time directly in Terminal:


log stream --predicate 'sender == &quot;the_name_of_your_app&quot;' --style compact


Press Ctrl-C to stop capturing process.