request to remove two empy p tags that collapse-o-matic inserts after each div

This is due to the lovely wpautop filter

You can try changing the execution priority of the dastardly wpautop filter by adding the following line to functions.php:

add_filter( 'the_content', 'wpautop', 20 );

Please do let us know if that solves it for you.

You are so right! That is obnoxious.

I tried your suggested code for functions.php, and it worked! But it broke some other stuff, such as interpreting line breaks in another plugin’s code as ‘<br \> tags.

But based on your revelation that the auto-p functionality in wordpress is the cause (thanks for linking to the other support thread where you explained it), I was able to work around the problem by removing line breaks after [/expand] and [/expandsub1], etc. Not pretty, but it works. Now I have lines like this:

Some content here.

[/expandsub1][/expand][/panel]More content begins here.

Thank you,
Joe

Glad it worked out for you Joe!
Issue marked as resolved.
Thank you very much for the kind review you wrote. We hare happy that you are happy. Yay! Everybody is happy!