Delete all your Tweets for free. Fast deletion has issues with Tampermonkey on Firefox, try ViolentMonkey.

1. Request a backup of your data https://x.com/settings/download_your_data
2. Download and unzip when it's ready
3. Open https://x.com/
4. A blue bar appears at the top of the page
4. Select the tweets.js file from your data export
8. Wait for all Tweets to be deleted