Change red text to the code below. Its basically changing uint8 to 16. Watch out for protocolgame tho, you'd need also to update the client src.
src/luascript.cpp
uint8_t mountId;
uint16_t mountId;
mountId = getNumber<uint8_t>(L, 2);
mountId = getNumber<uint16_t>(L, 2);
mount = g_game.mounts.getMountByID(getNumber<uint8_t>(L, 2));
mount = g_game.mounts.getMountByID(getNumber<uint16_t>(L, 2));
src/mounts.cpp
if (nodeId == 0 || nodeId > std::numeric_limits<uint8_t>::max()) {
if (nodeId == 0 || nodeId > std::numeric_limits<uint16_t>::max()) {
static_cast<uint8_t>(nodeId),
static_cast<uint16_t>(nodeId),...