If you change the grid color in the preferences and cick the Apply button, the color of all grids is updated now. So you can experiment while the Preferences Editor is open.
I have kept but moved the grid color button in the Draft_SelectPlane task panel for now. So that both options can be tested.
Related issue:
#5603
Previous PR:
#11010
* This PR implements the new PlaneGui class for the Draft_SelectPlane command.
* As mentioned in the previous PR, almost all working plane related code has been removed from gui_selectplane.py.
* The task panel has a new button "Next" to switch to the next working plane in the history.
* Both the "Previous" and "Next" buttons are only enabled if there is a corresponding step in the history.
* PlaneGui stores a working plane per 3D view, but the other commands have to be updated before that system is fully functional.
* Code to update the toolbar when switching to a different view will be added later.
Found via `codespell -q 3 -L aci,ake,aline,alle,alledges,alocation,als,ang,anid,ba,beginn,behaviour,bloaded,byteorder,calculater,cancelled,cancelling,cas,cascade,centimetre,childs,colour,colours,commen,currenty,dof,doubleclick,dum,eiter,elemente,feld,freez,hist,iff,indicies,initialisation,initialise,initialised,initialises,initialisiert,ist,kilometre,lod,mantatory,methode,metres,millimetre,modell,nd,noe,normale,normaly,nto,numer,oder,orgin,orginx,orginy,ot,pard,pres,programm,que,recurrance,rougly,seperator,serie,sinc,strack,substraction,te,thist,thru,tread,uint,unter,vertexes,wallthickness,whitespaces -S ./.git,*.po,*.ts,./ChangeLog.txt,./src/3rdParty,./src/Mod/Assembly/App/opendcm,./src/CXX,./src/zipios++,./src/Base/swig*,./src/Mod/Robot/App/kdl_cp,./src/Mod/Import/App/SCL,./src/WindowsInstaller,./src/Doc/FreeCAD.uml`
