XF 1.2 Continue Import from another browser / computer

If you have nearly 1 million threads (so by extension, many millions of posts), it will take some time.

You can continue it in another browser. You should be able to close the first one (wait a little bit to ensure the request completes) and then simply visit the Tools -> Import page. It will give you an option to continue (or abandon and start a new one).
 
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