In article ,
Bob Mannix wrote:
Of course this may not apply to yours but, in the open position it
should be possible to lever the door up off the bottom runner and then
move it out and down, releasing the top.

If you can do this, it's either an inferior design or been badly
installed. My Screwfix one has blocks specifically designed to stop this.

--
*Nothing is foolproof to a sufficiently talented fool.

Dave Plowman London SW 12
RIP Acorn