Maybe I’m going mad but I can’t edit white text that has been added to a Grid cell. I have a simple text box coloured orange with white text - double clicking the box to edit the text changes the box to white - then I’m unable to see my text.
Workaround: Place the text element as a child of a new div wrapper, using your background color for the wrapper. Or, highlight the text in the block using your cursor (from right to left) so it is visually selected. The former is a better solution.