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.
Well, I found an pretty easy solution to my problem at the end. It is a temporary solution, but it works. What I did was that I degraded my STM32CubeMX from 5.1.0 to 5.0.1. Something must have changed in the last version of STM32CubeMx.