Thereās always git bisection. Anyone who can compile their own binary and has at least an afternoon free can do a bisect to find the exact patch where a problem appeared. Itās time consuming, but thereās no programming skill required.
You basically tell it when the game last worked right for you, and when you first noticed it was broken, then It picks a midpoint between them and brings up that version of the code. You compile it, test, and then tell it if that point works or is broken, and you wash/rinse/repeat until youāve found exactly when it broke.