Does this mean someone could take ownership of this contract since it is public?

Question

I'm new to programming languages and trying to dive into solidity smart contracts, but does this mean that this contract could be taken over by anyone calling it due to it being public?

Sorry if this is a bad question

contract Ownable {
  address public owner;

  /**
    @dev The Ownable constructor sets the original `owner` of the contract to the sender
    account.
   /
  constructor() public {
    owner = msg.sender;
  }

  /**
    @dev Throws if called by any account other than the owner.
   /
  modifier onlyOwner() {
    require(msg.sender == owner, "Ownable: caller is not the owner");
    _;
  }

  /*
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
    @param newOwner The address to transfer ownership to.
   /
  function transferOwnership(address newOwner) external onlyOwner {
    if (newOwner != address(0)) {
      owner = newOwner;

Answer 1

No, this code is safe. constructor(...) is a special function, which can only be called once on the contract deployment to initialize the contract params.

After the constructor has run, the final code of the contract is deployed to the blockchain.

Ref: https://docs.soliditylang.org/en/v0.8.6/contracts.html#constructor

Answer 2

In fact what protects the contract ownership transfer is this line below:

modifier onlyOwner() {
  require(msg.sender == owner, "Ownable: caller is not the owner");
  _;
}

and then applied on the transferOwnership function

function transferOwnership(address newOwner) external onlyOwner {
  if (newOwner != address(0)) {
    owner = newOwner;
  }
} 

try remove onlyOwner from above function and anyone will can take ownership of this contract!