Block a comma separated list of bloggers
Tumblr Batch Block is an extension which allows you to block a lot of bloggers at once, without the hassle of doing it one at a time. As of v1.5, this extension also allows you to copy your blocklist to share or use on your sideblogs.
With this extension you can mitigate the damage of a harassment campaign by stopping the hate mail, potentially before it even starts.
If you find any bugs or wish to help with the development of this extension, please visit the official development page at https://github.com/realityfabric/Tumblr-Batch-Block