Remember and automatically activate a workbench based on the document tab selected.
RemBench is a FreeCAD module and can be installed with the FreeCAD Addon Manager.
Install path for FreeCAD modules depends on the operating system used.
Linux:
/home/user/.FreeCAD/Mod/RemBench/InitGui.py
macOS:
/Users/user_name/Library/Preferences/FreeCAD/Mod/RemBench/InitGui.py
Windows:
C:\Users\user_name\AppData\Roaming\FreeCAD\Mod\RemBench\InitGui.py
Once installed no additional configuration is needed. Select document tab and the desired workbench. Next time the document tab will get selected workbench will get set automatically. For convenience an enable or disable menu entry is provided under Accessories -> Remember workbench.
FreeCAD forum thread: https://forum.freecadweb.org/viewtopic.php?f=34&t=43387