This one is from an online article posted by John Cassidy, the fine New Yorker columnist, quoting another pundit on the Sessions firing. “This is a frontal assault on the Mueller investigation”, Susan Hennessey, the executive editor of the Lawfare blog, wrote on Twitter.  “Trump sees a window and he’s taking it.” This is a conflation of “sees an opening” and “window of opportunity”, both meaning a short period of time in which one has a favorable opportunity to do or accomplish something.  A window is an opening, and thus the reason for the mashup.  Kudos to John Costello for spotting this one and sending it in.