What you can see is technically water vapour as the hydrocarbon particles that the water vapour sticks to are microscopic and invisible to the nake eye. Chemtrails are caused by inefficient combustion. Not enough oxygen going into the fuel mix. Environmentalists have been trying to regulate the commercial airline industry for years to reduce this pollution but the industry has a lot of money and has created many disinformation campaigns and propaganda to comfuse people. Chemtrails are not related to cloud seeding or chat. Most of the disinformation is based on trying to confuse people to think they are all the same thing. Chemtrails are pollution. Cloud seeding is dropping salt into existing rain clouds to make them form droplets and cause rain to fall. Chaf is a mixture of metal shavings, fibre glass, and microplastics. Chaf is used by the military to block radars signals amd hide aircraft movements.