No option to change layer ID #4020

Why is this necessary, what is your use for sequential IDs? Layer IDs are a Tiled implementation detail and their specific value shouldn't matter as long as they remain unique within a map. If you are relying on layer IDs for something in your game, that is a mistake - use layer names or custom properties instead.

That said, I do wish Tiled assigned layer IDs sequentially based on the IDs currently in use, rather than always incrementing. This would avoid the need to store "nextlayerid" in map files, and it would prevent the IDs from getting silly large when layers are created and deleted repeatedly. I have some maps with perhaps a dozen layers with IDs in the hundreds if not thousands, and it just feels silly. It's not a "real" problem since, as I said, the IDs should not be treated as static or "important" (and in fact, could be randomised on each save without making them any less useful), but the IDs getting huge does bother me a bit.

Ditto for Objects, which have the same problem. With Objects, the IDs are done the way they are to prevent object references from accidentally referring to the wrong object when the values are changed, but I'd rather see IDs reused and no-longer-valid references cleared.

Coz is often fake and bad intuition due names in case code need int ID.. https://github.com/mapeditor/tiled/issues/4018

I think You are wrong.. coz .tmx should be like a data base and template, so if you building logic levels eg. 3 similar, then layers should be this same id for each. And when some mistake or something.. accidentally pushed add layer, etc. changing this data structure with no option to manage. I tried manually in file, but then app have problem with this.. as broken - probably I made this in bad way or it not allowing to some changes maybe.