Hello,
In STM32CubeIDE 1.14.0, setting another project as the default active project involves a straightforward process. Begin by navigating to the "Project Explorer" window, where you have the list of your projects. Right-click on the project you want to set as the default active project; in this case, project_3. From the context menu that appears, select "Set as Active" or "Set as Default." The exact wording may vary slightly depending on the IDE version.
Once you've done this, project_3 will be designated as the default active project. Keep in mind that this change affects the build and debug configurations, directing the IDE to focus on project_3 when you initiate build or debug processes. If needed, you can confirm the active project status by checking for visual cues such as bolded text or icons next to the project name in the "Project Explorer" window. This signifies that project_3 is now the default active project in STM32CubeIDE. If you encounter any issues or variations based on your specific version, referring to the official documentation for STM32CubeIDE can provide additional guidance.