Zooming in on topo images

You can zoom in on images when in the topo view that shows all the routes. However, when you go in to details of a single line, you can no longer zoom in, and tapping an image takes you back to the topo with all the lines. Very frustrating loop. Makes it hard to see the line/holds in a topo with a lot of routes, because overlapping (and very thick) route lines block the view.

Tldr; no way of zooming in on an image with only the route line of interest shown.