This is a tricky one... It's hard to tell what's actually going on here for trim based on the photos. It looks like they did tile into the window sill part of the window. Their installer most likely made "miter cuts" on the tile so there was a nice transition from backsplash to sill (see photo above).
For the other parts of the window, they may have used white metal "Schluter Strip" trim which can be very discreet. Or maybe the white grout is just covering up the exposed edges of the cut tiles.
If you didn't want to trim out your window in Schluter Strip or a window molding, we make tile trim! For field sizes (squares and rectangles) we can finish the actual tile with a glazed or bullnosed edge. If you're using a specialty shape, like the hexagons pictured here, a nice trim option is a 1x6 "flatliner" with either a glazed or bullnosed edge.
If you'd like to be connected with a Fireclay Design consultant, who can go over all of this is more detail and send additional imagery, just let me know what city + state you're reaching out from :-)
Fireclay Tile
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