The plug-in loads in Reaper and also in Bitwig without any problems on my Ubuntu 20.04 system. I don’t use the WebBrowser component. It also runs stable on macOS and windows.
A user uses the Zorin OS which should be similar to Ubunto 20.04. The plug-in works in Bitwig, all is good unless of some drag-and-drop issues.
But it crashes Reaper immediately without any crash log message when he tries to load the VST.
Edit: It works when he runs It in his process with “Run in a separate process”. It also works when he starts reaper with GDB.
The best way to be sure is to inspect the compiler invocations to see whether this option is included. You can use cmake --build <build-dir> --verbose to check. However, JUCE’s CMake should already enable hidden symbols for plugin targets, so I’d be surprised if that wasn’t happening for some reason.