Development tools for Zephyr on STM32Workbench for Zephyr: VS Code extension to set up, build, flash and debug Zephyr applications on STM32.Devicetree manager: browse, edit and visualize Zephyr devicetree, STM32CubeMX-like for Zephyr.
Not sure if this will help you ... I use latest version of Workbench with Eclipse Photon on Mac 10.14.1 and have no instability. I have two (large) projects, using different boards from STM32CubeMX generated projects.