My forum is behind a paywall, using Membermouse, so you won't be able to look at it, but I was getting help from Membermouse and they ran a diagnostic to see if they could find the origin of some random 504 errors I was getting while testing my forum set up (they aren't fatal, they just need a refresh), and he found this instead:

12-03-2022 18:47:18 (likely GMT -0700)
Uncaught Error: Call to a member function get_option_items_per_page() on null in /home4/debfillm/public_html/thereasonwelearn/wp-content/plugins/wpforo/wpforo.php:796
Stack trace:
#0 /home4/debfillm/public_html/thereasonwelearn/wp-content/plugins/wpforo/includes/hooks.php(218): wpforo\wpforo->init_current_object()
#1 /home4/debfillm/public_html/thereasonwelearn/wp-includes/shortcodes.php(355): wpforo\wpforo->{closure}(Array, '', 'wpforo')
#2 [internal function]: do_shortcode_tag(Array)
#3 /home4/debfillm/public_html/thereasonwelearn/wp-includes/shortcodes.php(227): preg_replace_callback('/\\[(\\[?)(wpforo...', 'do_shortcode_ta...', '[wpforo]')
#4 /home4/debfillm/public_html/thereasonwelearn/wp-content/themes/Divi/includes/builder/class-et-builder-element.php(3012): do_shortcode('[wpforo]')
#5 /home4/debfillm/public_html/thereasonwelearn/wp-includes/shortcodes.php(355): ET_Builder_Element->_render(Array, '[wpforo]', 'et_pb_text')
#6 [internal function]: do_shortcode_tag(Array)
​...

Does anyone know what this is? 

Also -- and this is weird, so bear with me -- I wonder if this could have anything to do with the fact that my WPForo page structure is super bizarro.

Here's what happened: 
I installed the plugin, built my whole forum, then accidentally deleted the forum page and was not able to restore it. I created a new forum page, found the board ID, and put it in with a shortcake, thinking that would solve the problem, but it didn't, or rather it it created a brand NEW forum page.

SO, now I have TWO.
One points to wpforo and is published
One points to wpforu shortcake with the board ID, and that one is a DRAFT

You would think the draft one has nothing to do with my success, but if I put it in the trash, the forum breaks. I don't appear to need to publish it for things to work, but this is very strange, and doesn't seem right.

I can't help but wonder if that issue above has something to do with my error. I have personally not seen this error come up in my testing, when using as admin or test user. 

Thoughts?