I made a modpack and tried to create a world, but my client sent me "Errors in currently selected datapacks prevented the world from loading. You can either try to load it with only vanilla data pack ("safe mode"), or go back to the title screen and fix it manually" but safe mod button do nothing.
I have my mods in a separate mods folder, but when I open up the datapacks screen from the world creation screen, all the mods are listed there.