Delete all LinkedIn posts version for June 2021.

delete-linkedin-posts.js

(() => {
  let speedMs = 500

  setInterval(() => {
    let dropdown = document.querySelector('.feed-shared-update-v2__control-menu .artdeco-dropdown button')

    dropdown.click()

    setTimeout(() => {
      let optionDel = dropdown.parentElement.parentElement.parentElement.querySelector('.option-delete .tap-target')
      
      if (optionDel === null) {
        setTimeout(() => { window.scrollTo(0,document.body.scrollHeight) }, speedMs * 4)
      } else {
        optionDel.click()
  
        setTimeout(() => {
          document.querySelector('.artdeco-modal .feed-shared-decision-modal__confirm-button').click()
        }, speedMs)
      }
    }, speedMs)
  }, speedMs)
})()

any web fren could do comments too? https://www.linkedin.com/in/{user_id}/recent-activity/comments/

Delete LinkedIn comments AND unlike posts

I used to use this one, while I was on LinkedIn. I don't know if it works today.
Open a profile page with your comments and run this bookmarklet. It will delete your comments AND unlike other posts at the same time. You can watch in console log how it goes.

Just be sure to change accountHref and accountName.

(() => {
  let speedMs = 500
  let accountHref = '/in/your-account-url/' // Change this to your account URL
  let accountName = 'Your Account Name' // Change this to your account name
  let nameMatch = new RegExp(accountName, 'gi')
  let commentNo = 0
  let likeNo = 0
  window.scrollTo(0, document.body.scrollHeight)

  setInterval(() => {
    setTimeout(() => {
      window.scrollTo(0, document.body.scrollHeight)
    }, speedMs * 4)

    let dropdown = document
      .querySelector(`.comments-post-meta a[href="${accountHref}"]`)
      .parentElement.parentElement.parentElement.querySelector(
        '.social-details-social-activity .artdeco-dropdown button'
      )

    let liked1 = document.querySelector('[aria-label^="Unlike"]')

    let liked2 = document.querySelector(
      '[aria-label^="Like"][aria-pressed="true"]'
    )

    if (dropdown !== null || liked1 !== null || liked2 !== null) {
      if (dropdown !== null && nameMatch.test(dropdown.innerHTML)) {
        dropdown.click()

        setTimeout(() => {
          let openDropdown =
            dropdown.parentElement.parentElement.parentElement.querySelectorAll(
              '.artdeco-dropdown__content ul li .option-button'
            )

          let deleteBtn = Array.from(openDropdown).filter(
            (item) => item.innerText === 'Delete'
          )

          setTimeout(() => {
            deleteBtn[0].click()

            setTimeout(() => {
              let modalButtons = document.querySelectorAll(
                '.artdeco-modal__actionbar button'
              )

              let modalDeleteBtn = Array.from(modalButtons).filter(
                (item) => item.innerText === 'Delete'
              )

              modalDeleteBtn[0].click()
              commentNo++
              console.log(`Deleted comment ${commentNo}`)
            }, speedMs)
          }, speedMs)
        }, speedMs)
      }

      if (liked1) {
        setTimeout(() => {
          liked1.click()
          liked1.remove()
          likeNo++
          console.info(`Unliked comment ${likeNo}`)
        }, speedMs)
      }

      if (liked2) {
        setTimeout(() => {
          liked2.click()
          liked2.remove()
          likeNo++
          console.info(`Unliked comment ${likeNo}`)
        }, speedMs)
      }
    } else {
      setTimeout(() => {
        window.scrollTo(0, document.body.scrollHeight)
      }, speedMs * 4)
    }
  }, speedMs)
})()

When you change this, minimize JS and then put that code in here and add it to bookmark URL.

javascript:/* PLACE MINIMIZED CODE HERE */;

You will need to run this several times, because LinkedIn doesn't display all of your content at once.