>>39
Variables and Expressions - Definition & Usage | AutoHotkey v2
https://www.autohotkey.com/docs/v2/Variables.htm
> A variable cannot be explicitly deleted, but its previous value can be released by assigning a new value, such as an empty string:

Variables and Expressions - Definition & Usage | AutoHotkey v2
https://www.autohotkey.com/docs/v2/Variables.htm#cap
> The memory occupied by a large variable can be freed by setting it equal to nothing, e.g. var := "".