Do NOT make a new grid

When a new grid is created, it becomes impossible to check for ALL changes when selecting a random option. Changes are made on the NEW grid, but the checking is done on only the OLD grid. This may lead to some unexpected and or strange bugs.

It would be better to keep using the same grid. Makes things just a little bit faster too. (little bit)

The issue does not name files, tests, or an entry point. Locate where a new grid is created and where random-option changes are checked; trace whether checks still read the old grid. Done means the existing grid is reused and all changes are checked against it without introducing the reported unexpected behavior.

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