What episode does lady bug and cat noir reveal they're true identities to each other?

Ladybug and Cat Noir reveal their true identities to each other in the episode titled "Truth," which is the 22nd episode of Season 4 of Miraculous: Tales of Ladybug & Cat Noir. In this episode, they confront their feelings and the complexities of their dual lives, leading to a significant moment of revelation. However, the episode also explores the consequences of this revelation and the challenges they face afterward.