If you want to delete all your old Twitter DMs (which I think is a good idea even if Twitter might retain copies of them somewhere), and also your historical likes, RTs, and any tweets you don’t want to keep, I made a Twitter app for that.
It’s called Semiphemeral and it’s pretty easy to use. I posted instructions for how to do it https://twitter.com/semiphemeral/status/1591258781098594304?s=46&t=L4aWvmyNxEFRL6eULgeO-A
Semiphemeral on Twitter

“As you watch in horror/delight as Elon burns this site to the ground you might be pondering your privacy 🤔. Do you have YEARS of tweets, likes, and DMs? https://t.co/EF6AVCPm2O Gather 'round, friends, while I show you how to DELETE THEM ALL (or as much as Twitter's API allows)”

Twitter
@micahflee does it delete them only from your own side of the conversation?
@micahflee Does this actually delete them? Many systems only flag things as "deleted" but keep them internally.
@micahflee Micah, is there a way to delete DMs in more than 30-day chunks?
@noahshachtman @micahflee doesn’t this only delete one side of the convo? I think with DMs they still live in the other person’s inbox unless they delete them as well
@taylorlorenz @noahshachtman @micahflee Twitter itself probably retains copies as well, at least for a while, but who could actually access those? it's not like the company is owned by an obsessive, thin-skinned power user...
@taylorlorenz legal data rights can help with the other side — if there’s anyone left to comply with the law. https://someone.elses.computer/@mikarv/109326253999130984
Michael Veale (@[email protected])

Twitter is now an insecure platform, haemmorhaging security experts. It could haemmorhage your DMs, through leak or sale. It's no hard guarantee, but your best chance to delete them is with is with #GDPR rights. I've written a blog on how: https://michae.lv/deleting-dms-from-twitter/

Someone Else's Computer

@taylorlorenz @noahshachtman @micahflee Yep, that's correct. Definitely just one side.

It also doesn't "sever" the conversation, so even if you remove all the DM messages on your side and lock your DMs, they can still reinitiate a conversation.

@micahflee Does this actually delete them on twitter's end or does it just remove your ability to see them?
@micahflee Thank you for this service. I'm trying it out now for DMs
@micahflee do you anything that’ll let me@grab my bird site bookmarks?

@niten @micahflee

NICE - this would be amazing - it's what I was wondering earlier. I want to pull off my bookmarks

@micahflee dude. This is amazing. Love it!

“In order to prevent fascists from using this free privacy service, Semiphemeral keeps track of Twitter accounts used by prominent racists, misogynists, antisemites, homophobes, neo-Nazis, and other fascists”

@micahflee Is this best for if you're leaving Twitter for good? I'm not sure I'm there quite yet - too many good connections there that aren't here yet.
@micahflee that only deletes them from your view. They are still visible to the recipients. DMs are only deleted from Twitter servers 30 days after you delete your Twitter account.
@micahflee Speaking of DMs, are you aware of any efforts to do e2e in Mastodon?

Let me see if I got this right:
I log in to your site with Twitter, your site uses my info to login and wipe my account. DMs, likes, tweets, whatever.

So... i give you permission to login to my account. 🙄

I will counter your offer by recommending the services of @OneFlySuit.
His methods require no account access & are guaranteed to be permanent.
All tweets, Dms, likes RTs, you name it... completely gone.

@micahflee I made a copy of my artisichope account on twitter just days before musk Took over. Now I can't make a copy. I wonder if anyone can. My lauraanntull account was banned for saying I hoped a guy who assaulted me suffered as much as I have. It wasn't a direct threat. The person who reported me then started email harassing me & said my assault was just a finger. I had been on Twitter since 2009 and had Over 1600 followers. I joined to help get american journalists out of north Korean. I think the Twitter take over is a political effort to effect our politics. I'm worried Twitter will change my lauraanntull posts to make me look like a monster. When I believe in un bill of rights.
@micahflee I tried this several times. Signed in and gave it permission the. It took me to a link that wanted me to open a zoom. So a massive fail for me I guess.
@micahflee thank you! Sitting in the queue right now. 😄
@micahflee With the caveat that it’s entirely possible (and quite likely) that your Twitter content has been archived somewhere.
@bigstormpicture @micahflee most likely after seeing the Cambridge analytica insanity
@micahflee I’ve had it for a few months, keeps my account clean. Thanks for setting it up! I need to remember to send you a donation.
@micahflee @hanscas dit ⬆️ is wellicht ook handig!
@teunemans
Ja, maar ja, om nou een bot toegang te geven tot je DM's... "Don't worry, I'm just a bot".
Ik heb hier toch ook mijn bedenkingen bij :)
@hanscas ook eens hoor. just feeling my way… ik ben zoekende.
@micahflee @mmasnick somehow it only downloaded 3500 tweets of mine?

@micahflee isn't it scam dear 😊

Should I...

@micahflee thanks for building this Micah, that was very convenient even for a one-time cleanup!
@micahflee good for the interface side! the law can help you target the copies of DMs Twitter retains using your data rights — have explained how here https://someone.elses.computer/@mikarv/109326253999130984
Michael Veale (@[email protected])

Twitter is now an insecure platform, haemmorhaging security experts. It could haemmorhage your DMs, through leak or sale. It's no hard guarantee, but your best chance to delete them is with is with #GDPR rights. I've written a blog on how: https://michae.lv/deleting-dms-from-twitter/

Someone Else's Computer
@micahflee Awesome, thank you for this link!
@micahflee Thank you for this. I'd already deleted all my DMs manually but will clean the nest of old bird droppings shortly.
@micahflee works like a charm, thanks!
Any clue why around 1/3rd is skipped?
@micahflee hmmm. I start to see, these are DM's Ithat require addional approval from me.
@micahflee Tried your tool a while back, and it was easy to use. Thanks!
Only problem: I belong to that group whose older tweets cannot be deleted through the API for some reason. Has that bug ever been solved?
@micahflee Hey Micah, any idea why a number of my older than 30 days DMs didn't delete? A lot did -- like maybe 80% -- but 20% didn't. And I mean DMs older than 30 days.
@micahflee I'm curious what would be the benefit of deleting this information? I'm honestly asking. Maybe I should be considering doing this myself...
@micahflee Thank you, that sounds very helpful. And necessary :(
@micahflee interesting idea to delete soon data from twitter to redige its interest hence value for many
@micahflee you are a lot cleverer than me.
Well done though
@micahflee any chance you can also delete "favorites"?
@micahflee thank you so much for this 😃