UBB.Dev
See this post
https://www.ubbdev.com/forum/showthreaded.php?Cat=0&Number=115254

I add one post (thread) and attach t1.jpg
and edit the post and attach t2.jpg , and t1.jpg remains on server ,
and edit the post and attach t3.jpg , and t1,t2.jpg remains on server ,
and edit the post and attach t4.jpg , and t1,t2,t3.jpg remains on server ,

If , you (admin / Scream ... or other staff) delete that post ,
You will find that only the last attachment (t4.jpg) be deleted .
And t1.jpg , t2.jpg , t3.jpg remain on server , become 'orphan' attachments.
If you check the delete attachment box while uploading the new one, does it leave it on the server as well?

And, um, bugs should be reported at http://www.ubbcentral.com so that they can be logged. This isn't an official site, and bugs reported here don't neccessarily getted considered when they're coding new versions.
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