In carpet client (1.12.2) there is a feature called "Snap Aim Keylocker" which, when snap aim is on, allows you to hold a key that when held blocks the game from registering key-up signals. It allows you to hold down keys to walk or place blocks, however it only functions when carpet client's snap aim is on-which is inconvenient, as tweakaroo has a better snap aim with overlay and adjustments and so on. It would be helpful as a separate tweak in tweakaroo.

A minor behavior thing is tweakaroo doesn't register those held keys for tweaks and whatnot-like fast place or flexible placement, it only works on vanilla inputs-and maybe if it was integrated into tweakaroo that would work? I do not know how the programming do the work yes