A public service announcement regarding tumblr’s content-source option:

July 20, 2011

The content-source option was added by tumblr so that you can link sources from outside of tumblr. External websites. Putting your own blogs url as the content source is unnecessary. Tumblr automatically adds the source link to the bottom of posts after 3rd level rebogs (reblogs of reblogs), and it does it in a way […]