In Hail Doofania!, Candace wears the clothes she mistakenly received from the dry cleaner, as though she only has one outfit. Previous episodes establish that she has a diverse selection of clothes but chooses not to wear them.
In "Out of Toon", after the boys' computer studio makes their movie, they set up an outdoor theater in their back yard to show their movie after the sun sets. However, the scene cuts to Perry and Dr. Doofenshmirtz dancing at DEI, and it's still daytime there.