That is the poorly named "myspace_popup" which displays the "My Account Menu."
Looking at your Shout Box tells me that a custom JavaScript somewhere on your page (probably with the header) has broken all the following JavaScript on it.
To fix the page display, debug or remove the custom JavaScript you've added.
edit:
since this is a new install, confirm that the files within your ubb_js/ are correct. This is where the stock UBB.threads JavaScript files live.
also confirm that your directory paths are correct, as they may not be pointing to the required ubb_js files.
Last edited by isaac; 01/08/2018 3:06 PM. Reason: updated for custom vs new install reference
