Yes, flick out the rubber gasket from inside, this allows the glass unit to rattle, from outside push the glass inward in all 4 corners and now remove the beads
Its fitted from outside so your safe but a good illustration on what happens when you tile over tiles, I've been to jobs where the tiles have covered the beads on an internal beaded system and now the customer wants the glass changing...............'you won't damage the tiles will you, they came from Italy specially', no love I won't because I'm not touching it.........see ya!
Yep your glass is fitted from the outside, if they want to try doing it through the top opener then fair play to them, again remove internal gasket, poke arm through top window and remove two side beads and top one blind(can be done and I've done it), leave bottom one in place(you couldn't reach it anyway unless you have arms like Mr Tickle), push the glass out and feed it back in through the window