twitter_trend_removal.js

// Add any trending topic in the next array and start using it. It has to be in lowercase
const blackListedKeywords = ['politics', 'entertainment', 'chumel'];

/**

Just copy and paste this code in your browser console and that's it.

NOTE:
- This code can be implemented as an extension, where the blackListedKeywords array can be created from items in the localStorage.
- The extension can have a small UI where users can enter their blacklisted keywords.
- There is a observer method, it helps to detect when Twitter inserts a new children node on the "What's happening section",
  so it can easily detect and remove a trending topic based on a keyword without reloading the page.
*/
const removeTrend = trend => trend.parentElement.removeChild(trend);

const isBlackListedKeyword = item => blackListedKeywords.some(keyword => item.innerText.toLowerCase().includes(keyword));

const removeBlackListedKeywords = () => {
  const trends = Array.from(document.querySelectorAll('[data-testid="trend"]'));
  const trendsToRemove = trends.filter(isBlackListedKeyword);

  trendsToRemove.forEach(removeTrend);
};

const nodesAdded = mutation => mutation.addedNodes.length > 0;

const checkForAddedNodes = mutation => nodesAdded(mutation) && removeBlackListedKeywords();

const observer = new MutationObserver(mutations => mutations.forEach(checkForAddedNodes));

const whatsHappeningSection = document.querySelector('[aria-label="Timeline: Trending now"]');

removeBlackListedKeywords();

observer.observe(whatsHappeningSection, { childList: true });

// uncomment the following lines to remove the "What's happening" sidebar
/*
const whatsHappeningSidebar = document.getElementById('accessible-list-0').parentElement;
whatsHappeningSidebar.parentElement.removeChild(whatsHappeningSidebar)
*/