My mouse suddenly behaves differently in Minecraft?

I use a normal mouse, but for an hour the mouse settings have changed somehow and I can no longer select the items in my inventory as they were. In the past I just had to click on the item and I had it. Now I have to hold down my left mouse button to hold it, otherwise I'll let it go. I can also no longer store individual items in the inventory (when holding with the mouse button) and the exchange of held items with the button in the inventory either, I have to put the first one down to get it.

Does anyone know why? Can you change it again or are there any tips with which I can do the things that worked before?

Download the version again.

Have you fed them yet

Deactivate the touchscreen mode in the controller.

Thank you very much, it worked.