in the older SMF, "remove" button is available to all messages iirc. as i said its random now, no correlation if its older post or not, to say it simpler, its interleaved between "got remove button" and "no remove button" (up to notify button only) messages, or about half the messages in currently displayed page can be deleted and another half cant, and interleaved (actually more cant than can). not necessarily the 1st msg in a thread, and not necessary with quote (my reply to others) inside. just checked: not necessarily someone replied to it, and even the 1st message in a thread got the "remove" button! just an example (i'm not intending to delete, just for example):
i
can't remove this message
from my profile, but i can remove when opened it from the thread:
https://www.eevblog.com/forum/index.php?topic=5865.msg76804#msg76804 (reply #9 in The perfect function generator, does it exist ? thread)
no one replied, i didnt quote, i can delete gracely without interrupting the thread flow if i want to. but i cant, from "show post" profile.
i
can remove this message
from my profile, and also i can remove when opened it from the thread:
https://www.eevblog.com/forum/index.php?topic=5890.msg77061#msg77061 (1st post in China LC200A LC Meter Teardown thread)