Question

[BazZziliuS]

Can I cancel this or that code that is being executed on me? For example, screengrab or crash attempt

Something like that

    if b:find("while true do end") then
        return
    end

[lewisclark]

Yep.

if gluasteal.SOURCE:find("while true do end") then
    return false
end

[BazZziliuS]

Yep.

if gluasteal.SOURCE:find("while true do end") then
    return false
end

Even without a hook?

[lewisclark]

Yep.

if gluasteal.SOURCE:find("while true do end") then
    return false
end

Even without a hook?

You don't need a hook to prevent while true do end from being executed on the client. Bear in mind that this is not a good way to prevent this sort of thing, though.

You would need some form of hook to prevent screen captures.