Some characters not allowed

I’ve tried to add this permalink:

my-awesome-post?awesomeness=99.9

or

my-awesome-post/?awesomeness=99.9

But it processes the characters as non-ascii alternatives:

my-awesome-post%3Fawesomeness%3D99.9
According to the doc, the only unsupported chars are:

UNSUPPORTED CHARACTERS
Following characters are no longer allowed in the permalinks.

<
>
{
}
|
“`
^
\
(
)
[
]

How can I achieve the slug format I’m trying to create?