I just did it in Sierra 10.12.5/Safari 10.1.1 by dragging the FTM URL to the little dot grid at the left of my favorites bar.

Edit: Or this, from Safari Help...

Quote:
Add a website to your Top Sites: Move the pointer over the Smart Search field, click and hold the One-Step Add button that appears at the left end of the field, then choose Top Sites from the menu.

You can also drag a URL or bookmark to the Top Sites page.

Last edited by artie505; 05/24/17 10:54 AM.
The new Great Equalizer is the SEND button.

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