I actually like this design choice. Having dealt with these kind of bugs, only to have to switch to the URL-safe base64 encoding, makes me really appreciate it.

I actually like this design choice. Having dealt with these kind of bugs, only to have to switch to the URL-safe base64 encoding, makes me really appreciate it. It forces the developer to consider which configuration they want, and in that, actually realize that there is a difference between URL-safe and the standard version.