How is that even...
Some forums have a rule which says you can't post in threads older than X time (e.g. one month). Breaking this rule, or generally replying to old thread, is called "thread necromancy", "necro-posting" etc. You just replied to a thread that was created on
Apr 25, 2016. The user that created it is no longer even active, thus your post might be considered useless and irrelevant (such posts are especially irrelevant, when they refer to something that isn't a thing anymore, but it's not the case here). Replying to years-old inactive threads is considered bad by many people (not me tho, if the post
adds something), and sometimes people go as far as prefer to make a new thread on the same topic, rather than continue the old one.
That's the thread necromancy. There's no rule forbidding it on this forum (no rules in general, actually), so we are just making jokes here.
Got it, kid? (I can't believe I had to explain this)