I mostly use a desktop browser and was wondering if there are any reliable extensions for Chrome or Firefox that let you download TikTok videos with just one click. Has anyone had success with any specific browser plugins?

There are others, but to be honest, I prefer to use https://snaptik.gdn because you don't have to install anything. Just open it in your browser, paste the TikTok URL and download. It's fast, and the video comes without watermarks. It's much safer than relying on random extensions that can affect your browser settings. In addition, it works on both desktop computers and mobile devices.