On the shop page I found out that the problem is the name attribute of the input type="radio" of the options. It is an array like name="bundle_option". When I edit the radio.phtml and set name="bundle_option" to all options, the page loads in 2 seconds.
I found another magento website which also has hundreds of options using this array but that page does not load slow. So there must be a solution for my problem. Can anyone help?
My config: Magento 2.1, All cache options enabled
To be more specific:
The product website loads fast but the product image and the bundle options take time to load - there's an icon instead of the content (loading circle).
Does the "Minify JS" option save some more seconds when switching to "production mode" (i use developer mode at the moment)?
I don't know if moving the JS from header to footer is an advantage in this situation. Does anyone have a tip?