I despise modern dual-flush push button toilets. It's been known for a while that, as a whole, they use more water than the traditional siphon flush cistern (WWP, if you're an old school plumber).
The siphon design cannot leak into the pan (unless the fill valve gets stuck and it overflows,but that's a different matter). The dual flush types have a below-waterline valve which inevitably starts to leak, giving a constant trickle of water into the pan. Obviously the fill valve keeps the cistern topped up, so you're just wasting water 24/7.
https://www.bbc.co.uk/news/uk-54326178
I will only have a siphonic flush. They are getting rarer as the human race forgets all the good stuff it learnt in the past.