[Solved]-Locking the zoom in on Mapview?-Highcharts

This is not possible with mapview and kinda defeats the purpose of the package. If you want this type of behaviour you either need to create the complete map using leaflet or at least create the base map with leaflet and then use it with mapview:

library(mapview)
library(leaflet)

map = leaflet(options = leafletOptions(minZoom = 12, maxZoom = 12)) %>%
  addTiles()
mapview(franconia, map = map)