Found the instructions on the item class file for this. Follow the simple and few steps to make your b2evolution RDF/RSS.92/RSS1/RSS2/Atom1.0 feeds show the full content of your post.
Why you should do that? Most feed readers subscribe because they want to read your content and to avoid opening a new window or tab just to visit your site. Additionally, they subscribe to your feeds so they will see all your new posts. Making them or rather forcing them to click on “read more” actually drives them away from the rest of your posts for that period. In other words, you get less exposure and loyal readers
So read on, if you are reading this from the blogsite itself.
Follow up:
Single file to touch, the file _main.php of every feed platform you want (feeds are in the skin format in b2evolution).
For Atom feed:
Search for:
echo make_rel_links_abs( $Item-[gt]get_content() );
And change it to:
echo make_rel_links_abs( $Item-[gt]get_content( 1, true ) );
For RSS1.0:
Search for:
$content = $Item-[gt]get_content( 1, false, T_('[...] Read more!'), '', '', '', 'entityencoded' );
And change it to:
$content = $Item-[gt]get_content( 1, true, T_('[...] Read more!'), '', '', '', 'entityencoded' );
For RSS2.0 and RDF/RSS0.92
Search for:
$content = $Item-[gt]get_content( 1, false, T_('[...] Read more!'), '', '', '', 'xml', $rss_excerpt_length );
and
echo make_rel_links_abs( $Item-[gt]get_content() );
Change it to:
$content = $Item-[gt]get_content( 1, true, T_('[...] Read more!'), '', '', '', 'xml', $rss_excerpt_length );
and
echo make_rel_links_abs( $Item-[gt]get_content( 1, true ) );
respectively.
Then upload your updated feed-skin files to your live or production site.
Thanks to Yabba and Stk for “summat”
And to my desperation to switch, and of course to the Atom platform team – I finally took time to figure this out.