I added a KML file realized I missed a plane so removed them via Contents -> Remove All Tracks then saved the the Sitch via File -> Save.

Nothing about the long-named KML file appeared in the save progress pop up.

I dragged the new KML file onto the window, but the points were static. They didn't move when playing or scrubbing the time line.

I did a File -> Save to save the new KML and refreshed the URL vis the browser reload button.

Once the page loaded, it seems like the old KML (that shouldn't have been saved, right?) was loaded along with the new KML file. The planes are duplicated except for N711HK which is the new one I added in the new file.

https://www.metabunk.org/sitrec/?custom=20018/planes seattle wa/20260313_013130.js