I've had this wish for a long time. Now that is realized.
The weight of the sockets and the lamps was too big for me.
PMMA is somewhat elastic. Glass not. It will eventually break.
I really wanted to avoid this "WTC effect".
before: glass shelves
after replacement: PMMA shelves
Now I'm calm again.
The new PMMA shelves are 8mm thick and polished on the sides.
A safe investment for me.