The "simple work around" is to open the Drupal BBB content type as a new window or new tab via "other mouse button -> click -> open new tab/window" on "Attend Meetings" (or "Moderate Meeting" if the Drupal user has appropriate permissions).
This was reported for the case of using Drupal "Blocks" within the Drupal v7.x of the BBB module with the following
Drupal bug report. However, and as noted, Menu Tabs are a different thing it seems here.
I have opened a "
feature request" to address Menus doing similar versus Blocks.
HTH.
--- Crawford