If you place a block on the obsidian spawning platform in the end it is completely deleted once you leave the end. I had a shulker box placed there, and upon going home for supplies and returning it deleted hundreds of hours of my work from a single glitch.
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If this is a issue and will be fixed, we will need to find other way to make a obsidian farm.
would this duplicate MC-902?

Correct.
I believe this is intentional as you want some temporary safety time when going through a portal (but also quite useful for some traps that I've made), however, the items should at least drop when coming through the portal.