Another thing: The replace tool should change elements back to their default properties, like it used to. The current behaviour (only changing the type, leaving everything else unchanged) can be replicated with PROP (type).
This is definitely not new since 95.0 (I have not tried 95.0 yet and cannot even confirm that this still happens there), but for quite some time, I had a feeling that ambient heat simulation causes warm air to rise even when gravity is disabled. I cannot /quite/ confirm this, but it seems to be visible in a few of the simulations I made, e.g. the exhaust plume of this rocket engine tending slightly towards the top: ID:2508743. It has been this way for as long as I can remember, and slightly annoyed my perfectionist side. But the effect is very subtle and does not affect actual gameplay for me.