Messy elevation lines when zooming

Hello,

I am using a Locus Map Classic app with offline maps. I just realized that the elevation lines gets multiplied and causes messy map view when I heavily zoom-in or zoom-out back and forth. I mean the map looks OK. Then zoom-in almost to max then zoom back. Same symptom if zoom-out a lot then zoom back to original. The map view gets messy.

It is reproducible whit different maps and themes as well hence I assume this is an issue with the application.