The JIRA request for this is here: My request for a bridge to bridge two (or perhaps more) installations of vBulletin was interpreted as "share database between sites".
A bridge would enable you to purchase multiple vB licenses and install them on separate TLDs to showcase different kinds of content, branded or presented in different ways. vB would benefit from additional license purchases, licensees would benefit from being able to create multifaceted communities with different kinds of content using more than just one top level domain.
A bridge is not an unusual thing and they exist (supported) for other types of software. To bridge vBulletin with e.g. wordpress or joomla, and keep the bridge updated alongside new versions would be difficult. A bridge for two versions of the same software from the same stable would be easier to deliver and keep updated.
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