replace with URLSearchParams

[yoshuawuyts]

Probably when IE catches up; not usable quite yet at the moment - https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams

[yoshuawuyts]

Annnnd, it still hasn't caught up :/

[yoshuawuyts]

Booyah, implemented last month https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/8993198/ — should be included in a soonish Edge build. Probably can start using this around this time next year :D