As far as I know there is no real consensus. Nurses like me like to do something - anything so tend to deroof the blister and dress it.
I think if the blister is intact leave it - unless the pressure in it causes pain in which case puncture it with a stril needle and then leave it.
If the blister bursts deroof it ( remove the unattached skin) and dress it with a hydrocolloid dressing ( compeed or similar)
Unless of course you are in the middle of a trek when you need to dress it in such a way as to prevent further friction - in which case the compeed might do but I tend to go for a fabric dressing well stuck to the foot to reduce friction and take care of healing after the walking is completed