Which files usually get over-written during vBulletin upgrades?

[TWood]

I modified one of the back-end files (includes/class_bbcode.php) as described here:

https://vborg.vbsupport.ru/showthread.php?t=208436

It now makes links open in the same browser window.

Is there a 'preferred' way to set these files that I modify apart from being over-written during a vBulletin version upgrade, or should I just keep a list?

[Lynne]

Keep a list. I also always do a mass compare between my old files and new files before an upgrade, but a list also helps.