How to change the sheet tab look?

I have been using LibreOffice version 5 for years, and only recently upgraded to version 7. In new version, sheet names in Calc no longer have border around them - selected sheet tab looks slightly different, while there is only white space between names of unselected ones. This makes it difficult for me to find the one I am looking for in a document with many sheets. Is there a way to turn on border around sheet names, or at least just a vertical separator line between them? It would make it easier to navigate.
I have only found a way to change the colour of tabs, so I could create contrast in this way (first sheet light, second sheet dark…) but that seem unnecessary labourious.

No, there isn’t.