OpenCPN is a free software (GPLv2) project to create a concise chart plotter and navigation software, for use underway or as a planning tool. OpenCPN is developed by a team of active sailors using real world conditions for program testing and refinement. If you are upgrading or installing new, OpenCPN 5.2.x needs wxGTK3 to be built with webkit support. So you will have to install webkit2gtk, available here at SBo, then build and install wxGTK3.