Unable to run CKEditor 5 due to deprecated prototype.js dependency breaking native APIs

Just for the record, this is a follow–up of the original issue submitted by one of the users on our CKEditor 5 bug tracker.

We noticed that your software uses the prototype.js library, which has been abandoned years ago, obsoleted and can be considered an antipattern by modern programming standards because of the way it was implemented.

The prototype.js library extends native objects like `Array` and provides own implementations of various methods, which made sense back when browser vendors were slow to follow the standards. But because the library has been abandoned and the web moved forwards, the implementations do not work with new technologies, for instance new data structures brought by ES6 and fall short, breaking applications like CKEditor 5 which strongly depend on them (other modern libs too, that's for sure).

Since CKEditor 4 is used extensively in the project and CKEditor 5 has been released earlier this year, some of the users may consider migration to the new editor a good idea. For instance, to benefit from its unique features (like real–time document collaboration). And just like in the issue I mentioned at the very beginning, they are going to face the issue of prototype.js taking over the environment, making it impossible to run CKEditor 5.

Do you have any plans to move away from prototype.js? Do you have any other ideas how to make it easier for the users to run CKEditor 5 in your project?

Thanks,
Aleksander from CKSource