If your window has no casing but a blind, mini-blind curtain rod brackets are also a good alternative to fixed brackets. On a scale of 1 to 10, I'd give these options 9 or 10.

NONO Bracket - Outside Mounted Blinds Curtain Rod Bracket Attachment (Set of 3) The NoNo Bracket Company 3508 ratings View Product Buy it on Amazon More info 1 ...

The SwitchBot Curtain 3 is compatible with curtain rods ranging from 0.59 to 1.57 inches in diameter, while the Aqara Curtain Driver E1 works with a smaller range of 0.98 to 1.26 inches in diameter.

This is why SwitchBot’s $135.59 Curtain Rod 2 caught my attention (most people will likely want two to open each curtain, bringing the total to $271.18 for one set, which is still pretty expensive).

The bracket-less mount lets you pull the curtain all the way around to the gap between your wall and the rod. The center rod extends from 38-72 inches and the sides from 20-37 inches.