Searching for the topic/post by ID? if copy/pasted literally will, if I understand you correctly, do exactly what you’re after. The topic title doesn’t have to be correct in the URL.
From one of our FAQs:
/t/<topic_name>{/<topic_id>{/<post_id>}}}
- Bog-standard link to a post.
topic_nameis largely ignored iftopic_idis present and valid. - Omitting the
post_idwill send you to the first post of the topic. - Visiting
post_id1will (by default) result in the URL in the address bar being re-written to remove it (i.e. it collapses to the above.) - Visitng
post_idof a large number not present will send you to the end of the topic - Omitting
topic_idwill send you to the topic iftopic_nameis valid,404otherwise