MUI DataGrid in SPFX solutions
	
I used Material UI DataGrid (@mui/x-data-grid": "^7.12.1") in SharePoint spfx webpart solution. Obviously, that wasn’t a good decision, but too much was already done.
The difficulties are:
1. The usage of SharePoint theme colors. It’s not impossible, but hard. Get ready for hard CSS implementations. If you use CSS classes, almost always you have to use !important.
.spDataGrid  {
  color: "[theme: themePrimary, default: #f5f3f3]" !important;
}
Common properties of DataGrid are not applied or do not work properly. For example, I set ‘editable: false’ to all the cells, but when you click a cell, it is selected.
disableColumnSelector, 
 	isCellEditable={(params) => false }
onCellClick={(params, event) => {
                event.stopPropagation(); // Prevent cell selection
              }}
All these properties should disable the editing mode, but the selected cell was just like ready for the editing mode. I didn’t want that. To disable the editing mode I used this ‘crutch’. In the styles of the DataGrid I disabled the outline.
              sx={{
                        width: 'auto',
                        "& .MuiDataGrid-columnHeaderTitle": {
                            whiteSpace: "normal",
                            lineHeight: "normal",
                            alignSelf: 'center',
                        },
                        '& .MuiDataGrid-cell:focus': {
                            outline: 'none',
                        },
                        '& .MuiDataGrid-cell.Mui-selected': {
                            backgroundColor: 'inherit',
                        },
                        '& .MuiDataGrid-cell': {
                            userSelect: 'none',
                        },
                    }}
There are also other difficulties, for example, the color of the Icon for a Boolean column. I also had to overwrite it with 'renderCell' property, but that was less obvious, than the editable cells.

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