Firefox txt broken semi fix?

[GoroFourArms]

I use to be able to open txt files in firefox and be able to use foxreplace but one of the recent firefox updates broke it. I noticed that when I open the inspector the html all the text is under the pre tag and when I change pre to p in the inspector everything works again.

I don't know if this is helpful at all since I am an amateur but I thought it would bring up to someone who might know better. So they can make a more permanent fix.