Thanks for the details! Now I know what is happening. I mistakenly thought you were using SteemKeychain. SteemLogin should currently not be allowed for this feature, because I don't use their JS API and just redirect to their page with the transaction to broadcast (no event to receive the broadcast result available).

As you already signed in to SteemWorld, you don't need to use SteemLogin or any other tools for broadcasting a vote. I guess, you enabled 'Settings -> Security -> Use SteemLogin For Signing'. If you disable this temporarily, it should work as expected. I will update SteemWorld later today, so that it will no longer use SteemLogin for the Copy Votes tool.