Hi! You've noticed one of the new additions to the forum...
To answer your question I will quote from the vBulletin announcement:
For more information on what's changed and what's new, please see this thread:Multi-Quote
The much-requested multi-quote feature allows users to tag multiple posts that they wish to respond to by clicking a small button on each post. Once the user clicks the reply button, each tagged post is quoted.
To increase usability, by default, only posts within the current thread are automatically quoted. If you wish to quote posts in other threads with multi-quote, you simply need to click a link on the reply page, and the text of those posts will be added without a reload.
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