Is there any chrome or firefox extension that can do this? I am managing A Tumblr network of 40+ accounts manually and logging in and out of all of them one by one to post links is not a good idea. I am looking for a browser extension that would add my private proxies to it and will allow me to shift from one to another while using different accounts. Most of the proxy extensions use their own proxies. Any help in this regard will be appreciated. Any other relevant idea or option is also welcome.