Rename projects ..Does that work ?
So, it looks like this is not high in their priority list. But thanks for the link to Andy Brown's site, in which he explains how to duplicate an Eclipse project.
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Development tools for Zephyr on STM32
Workbench 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.