Will adding additional base contract during UUPS upgrade, corrupt contract storage?

Support
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1

I have an ERC20 contract which is UUPS upgradeable, and I would like to add ERC20Votes.sol to this contract. Is it possible to add a new base class to a contract during upgrade, without messing up the contract's storage? Here is what my contract looks like now:

contract myToken is ERC20BurnableUpgradeable, OwnableUpgradeable, UUPSUpgradeable, PausableUpgradeable {

    struct TotalAllocation {
        uint256 firstAllocation;
        uint256 monthlyAllocation;
    }

    mapping(address => uint256) public totalSpent;
    mapping(address => TotalAllocation) public allocations;
    mapping(address => bool) public isWhitelisted;
    
    uint256 whitelistAddEnd; //time when you can no longer update the whitelist
    uint256 public deploymentTime;
    address public veTokenMigrator;

    // Reserved storage space to allow for layout changes in the future from upgrading.
    uint256[50] __gap;

    event AddToWhitelist(address[] accounts, TotalAllocation[] allocation);
    event RemoveFromWhitelist(address[] accounts);
    event VeTokenMigratorSet(address veTokenMigrator);

    constructor(){}

I want to change my contract to also inherit ERC20Votes.sol

contract myToken is ERC20BurnableUpgradeable, OwnableUpgradeable, UUPSUpgradeable, PausableUpgradeable, ERC20Votes {
  ... rest of code
2

I think it's fine, so long as you inherit it last.

There might be an issue if that additional base contract inherits itself some of the other base contracts that your contract inherits, so you might want to conduct a separate research on that if relevant.

BTW, shouldn't your gap be 44 (50 minus 6 slots)?