Google Docs: A Google App script for deleting all bookmarks from a Google Doc

gistfile1.txt

// 1. Tools > Script editor...
// 2. Paste the below code
// 3. Run
// 4. Approve permissions
// 5. Go to the document from which Script editor was launched and allow the script to run

function deleteAllBookmarks() {
  var ui = DocumentApp.getUi();
  var response = ui.alert('This will delete ALL bookmarks in this document. Are you sure you want to continue?', ui.ButtonSet.YES_NO);
  
  if (response == ui.Button.YES) {
    var doc = DocumentApp.getActiveDocument();
    var bookmarks = doc.getBookmarks();
    for (var i = 0; i < bookmarks.length - 1; i++) {
      bookmarks[i].remove();
    }
  }  
}

This script also works in the console; however, you may need to scroll through multiple pages to ensure they're all removed.

document.querySelectorAll('.kix-bookmarkicon-icon-outer').forEach(el => {
    try {
        let ev = getEventListeners(el)
        ev.mousedown[0].listener(el)
        ev.mousedown[1].listener(el)
        document.querySelectorAll('.kix-bookmark-bubble-button[data-tooltip="Remove"]').forEach(_ => _.click())
    } catch (error) {
        console.log("error on el: ", el) // likely means scrolling, can i automate this?
    }
})