Window covering and mounting assembly therefor

An extensible mounting assembly for a window covering, comprising:

• a headrail;
• a carriage within the headrail at an end of the headrail;
• a movable portion positioned in the carriage and configured to move relative to the carriage between a retracted position and an extended position;
• a cam rotatably coupled to the carriage and configured to contact the movable portion, wherein rotation of the cam relative to the movable portion causes the movable portion to move between the extended position and the retracted position;
• a flange extending from the cam and configured to maintain the cam in the carriage by holding the cam in place relative to the movable portion;
• a lever extending from the cam and being fixed to the cam, wherein rotation of the lever and cam together causes the movable portion to extend and press against a window casing to secure the headrail to the window casing;
• and
• a biasing member between the cam and the movable portion and configured to maintain the cam and movable portion in contact as the lever and cam rotate and to maintain the flange in place relative to the movable portion.