Switch Twitter Accounts in Safari?
Solution 1:
There is no add-ons on Safari who is doing that.
Chrome : https://chrome.google.com/webstore/detail/swap-my-cookies/dffhipnliikkblkhpjapbecpmoilcama
Mozilla : https://addons.mozilla.org/fr/firefox/addon/cookieswap/
By the way, I think you have to post your wish here : https://www.reddit.com/r/SomebodyMakeThis/