JUST TAKE A SCREENSHOT

If you see tags that someone else left on a post and want to share them with your followers (or anyone else who chances across your blog), please, please, PLEASE: don't use "prev tags," or "previous tags" or "prev prev tags" or any variation that may occur to you at the moment you're making that decision.

The very best way on Tumblr to:

• share that information in the tags with people who follow you, or
• continue a conversation that the person who said that thing in the tags, or
• let everyone know how hard you're cackling at a joke someone made, or
• whatever other reason you're drawing attention to someone else's tags

is to actually add the tag in question to the version of the post as it will appear when you reblog it. A screenshot is the most durable way to do this, since it gets included in all the downstream reblogs from your own, but if you don't want that for some reason, just replicate the actual tag in question in the tags of your reblog. If you're absolutely, vehemently against the screenshot, including the tags in question could look like this:

or like this:

OP has some really great tags:

#cool additional commentary tangential to the original topic #user who added the tags didn't include them in the body of the post but you thought they were important

and I think everyone should see them

The biggest reason to do this is that nobody wants a scavenger hunt. This is especially true when the tags in question are from more than one reblog down the line, or ones that you found in the notes on a different reblog chain.

The other big reason is the durability thing mentioned earlier. Maybe the tags you're enamored with came from OP, and they decided they didn't want notifications from the post anymore and deleted it. If you used "omg OP's tags 😹" with no further clarification, that information is lost forever when OP deletes the post. Same case if OP (or the person you reblogged from) deactivates, or gets deactivated. Actually including the tags in question makes sure that as long as someone is viewing it on your blog (or on any downstream reblog from you, if you used a screenshot) they can see the same thing you did.

Using "prev tags" instead of actually including the tags you're talking about results in a significant decrease in the usability of the website. Please, just screenshot the tags, or reproduce them in your post.