When you use the TOR browser or even any VPN then usually you will have this difficulties.
For me, I still don't get any hassle on logging in even while using VPN. Because based on my experience, I'm just spending less than 5 mins. only everytime I log in here from filling up the username and password up to solving captchas.
Note: disregarding the fact that I have an unstable internet connection sometimes.
(Always stay logged in). You will not need to login again. Of-course you want to make sure that your PC is protected and no one else (untrustworthy) is using the PC.
@OP ~ if you are tired of this then do what sir mdayonliner said, that was very effective. That's what I always do and I guarantee that you will now be free from those annoying captchas for real. Here's a tip, aside from not allowing others to use your smartphone/computer, never ever also log in your account in a computer rental shop. That was a very risky move since you can't assure that there's no keylogger installed to those computers.