Post History

Since there seem to be no userscripts for this, I wrote one myself. It should work with all major userscript managers and browsers.
The script prevents the `dragstart` event and thus drag and drop for the channel list. Additionally, there is a button to reactivate drag and drop if you want to rearrange the channels or drag users to different language channels without reloading the page.

```javascript
// ==UserScript==
// @name         Discord channel drag and drop disabler
// @version      1.0
// @description  Disables channel drag and drop in Discord web app
// @author       Zer0
// @match        https://discord.com/**
// @grant        none
// ==/UserScript==

(async () => {
    'use strict';
    
    function modifyChannelList(channelListElement) {
        let dragEnabled = false;

        // Add container element
        const container = document.createElement('div');
        container.style.paddingLeft = '8px';
        container.style.paddingBottom = '8px';
        channelListElement.appendChild(container);
        
        // Add toggle button with discord-like styling
        const toggleButton = document.createElement('button');
        toggleButton.style.color = '#FFF';
        toggleButton.style.backgroundColor = 'rgb(71, 82, 196)';
        toggleButton.style.borderRadius = '3px';
        toggleButton.style.padding = '2px 16px';
        toggleButton.style.width = '100%';
        function updateButton(enabled) {
            toggleButton.innerHTML = enabled ? 'Disabled Drag and Drop' : 'Enable Drag and Drop';
        }
        updateButton(dragEnabled);
        toggleButton.addEventListener('click', () => {
            dragEnabled = !dragEnabled;
            updateButton(dragEnabled);
        });
        container.appendChild(toggleButton);

        function addDragHandler(elements) {
            elements.forEach(e => {
                e.addEventListener('dragstart', ev => {
                    if (!dragEnabled) {
                        // Prevent channel drag and drop
                        ev.stopImmediatePropagation();
                        // Prevent link drag and drop (browser default)
                        ev.preventDefault();
                    }
                });
            });
        }
        // Add custom drag handler to all channel elements
        addDragHandler(channelListElement.querySelectorAll('li'));

        // Add custom drag handler to all future channel elements (when a new channel is created)
        const observer = new MutationObserver(m => addDragHandler(m.flatMap(e => [...e.addedNodes]).filter(e => e instanceof HTMLElement && e.tagName === 'LI')));
        observer.observe(channelListElement, { childList: true, subtree: true });

        return () => observer.disconnect();
    }


    let channels = document.getElementById('channels');
    let cleanup = null;

    if (channels) {
        cleanup = modifyChannelList(channels);
    }

    // Searches for the channel list element if the site changes
    const mainObserver = new MutationObserver(() => { 
        const newChannels = document.getElementById('channels');
        if (newChannels !== null && channels !== newChannels) {
            channels = newChannels;
            if (cleanup) {
                cleanup();
            }
            cleanup = modifyChannelList(channels);
        }
    });
    mainObserver.observe(document.body, { childList: true, subtree: true });
})();
```