UGUI Dropdown 1000 items very slow

I’m try to list all the system font I have installed,and select from list to view.
The problem is Dropdown perform very slow,how can I fix the performance problem?
Any switch to turn on to speed it up?

I would question why you need 1000 fonts. Are you trying to release an app with 1k fonts that you are able to release with a commercial product?

If you really need that much, you may have to look into a custom design. No, there is no switch.

I dont need them all,I just download some font package from Internet to test dynamic font in Unity
The font is not a problem,my question is how to deal with 1000 item performance of Dropdown/Combox

Is the problem with instantiating all of the font gameobjects, or with performance after they are loaded? If it is instantiation you might be able to setup the drop down with 1000 or so elements in the saved scene, then iterate and set them up at runtime, adding and removing as necessary based on the players system fonts.