Great you found the problem! Thank you. There was the same issue before:
But I used the dark theme so everything worked as expected.
Where the css expert how can help here? 
Or should we upgrade tabulator.js? There are some interesting new features (like persistent layouts) and may different designs.
or I try a simple copy paste? But these are all for version 4.7 and I thing ui-table uses 4.2
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