Directions line doesn’t scale correctly

The directions line on the map doesn’t scale very well when the map zooms in and out. It seems to adjust thickness in chunks as opposed to adjusting the whole line. Design wise it doesn’t look very nice and is kinda distracting, for me at least.

No file, test, or entry point is identified in the issue. Start by locating the map directions-line rendering and its zoom-handling path, then reproduce the behavior while zooming in and out. Done should mean the line thickness changes smoothly rather than in visible chunks and no longer distracts during zooming.

Written by the indexing model from the issue text.