Curly-brace-enclosed comma does not remove unwanted space after comma

[OskarPersson]

In LaTeX, one can remove unwanted spacing after a comma by writing "{,}" and is an important use in cultures that use commas as decimal separators. This does not work in SwiftMath.

For the following code I expect the first "1,5" to be written without any spacing after the comma.

$x_i\in[-1{,}5;1,5]$

Expected:

Actual: