Take Advantage of Browser Extensions
As with any other Chrome extension, find a Tumblr extension and click on the wrench icon in the top right of your browser. Select Tools > Extensions, then click Get More Extensions. From here you can do a search for Tumblr, which will display dozens of options. A popular option is Tumblr Dashboard. Once you add it to your browser and you’ve logged in to your blog, you can get a quick look at the blogs you follow by clicking the T icon in the toolbar. This opens a pop-up that also lets you reblog, like a post, or quickly blog about the Web page you’re on.
You’ll find add-ons by clicking the Firefox drop-down menu on the top left of your browser window and selecting Add-Ons. From the dashboard, a search will produce tons of results. One such is Tumblr Post, which lets you post photos, videos, mp3s, quotes and links to your tumblelogs by dragging and dropping content onto the extension’s status bar icon. You can also right click the icon in the status bar to post manually.