This is the universal method that works for PS3 consoles (Fat, Slim, and Super Slim), whether stock or modded.

: Forces the system to recognize newly added custom stores, icons, or DLC that didn't appear after a standard installation. The "Rebuild Database" Application (PKG)

When you install a PKG, the PS3 writes dozens of entries into the database. If a PKG is incomplete, unsigned (on OFW), or conflicts with existing data, it leaves "orphaned entries." The PS3 still tries to reference these entries during boot, causing lag, errors, or crashes. This is where a becomes essential.

Yes. PS3HEN works on OFW. Safe Mode is available regardless of HEN installation.