I\'m looking for a solution that creates object keys (is that worded correctly?) dynamically.
Arbitrary example, but this works in chrome and firefox
IE11 is not a "modern" web browser in the same way Chrome, Firefox or even Edge is. It doesn't support the new "object literal extensions" from ES6 (ES2015).
The syntax you are using is called "computed property keys", you cannot use it in IE11. You need to do this the "old fashioned" way.
var weeks = {};
for(var i = 0; i < 5; i++){
var tmp = {};
tmp["week" + i] = i*2;
$.extend(weeks, tmp);
}