The bug

The item form of lit redstone lamps ends up being deleted completely from worlds if any world which contains one is upgraded to 1.18.2 or whatever the current version is.

As with MC-249703 and MC-249849, this isn't any ordinary unsupported item, as lit redstone lamps were obtainable in Survival for almost two whole years since their introduction (MC-3973), before ultimately being removed in 1.7.2. Lit redstone lamps do differ from invalid data value leaves and lit furnaces in that they do appear visually distinct from the normal thing in item form, but that doesn't change much; MC-30940's comments section contains multiple testimonies from users who have used lit redstone lamps and other such invalid items for decorative uses and have suffered world corruptions as a result. Given how long this item was obtainable for, it's certainly not out of the question that a player from 1.2 to 1.6.4 will have collected lit redstone lamp items (either intentionally or accidentally, perhaps having not paid attention to it being lit in item form), left the game for a decade or so, and then loaded their old world up in the current version only to find all of those collected redstone lamps completely AWOL. This is not desirable behaviour.

How to reproduce

1. Create a world in any version from 1.2 to 1.6.4
2. Place a redstone lamp
3. Power this redstone lamp
4. Break the redstone lamp using a Silk Touch tool in Survival mode
5. Load this world in the latest version, e.g. 1.18.2

Expected results

The lit redstone lamp items would remain in the world in some form. Either they would be converted straight to normal redstone lamp items (keeps survival worlds "legitimate"), or they would become redstone lamp items with a BlockStateTag which sets the lit state to true (preserves prior behaviour, and additionally allows for their collection as a souvenir).

Actual results

Completely gone.