وَلَا يُصَلَّى عَلَى مَيِّتٍ فِي مَسْجِدٍ جَمَاعَةً.
Translation: A funeral prayer for the deceased is not to be offered in a mosque in congregation, according to this text.
This wording is discussed in Hanafi law under the disapproval of holding a funeral prayer inside a mosque; it should not be automatically turned into a claim that the prayer is invalid.
Modern mosque layouts and adjoining funeral areas can present distinct cases. The source rule should be distinguished from detailed practical fatwa applications.